/src/DLXEmu/external/imgui/imgui.cpp

Source (jump to first uncovered line)
// dear imgui, v1.90 WIP
// (main code and documentation)

// Help:
// - See links below.
// - Call and read ImGui::ShowDemoWindow() in imgui_demo.cpp. All applications in examples/ are doing that.
// - Read top of imgui.cpp for more details, links and comments.

// Resources:
// - FAQ                   https://dearimgui.com/faq
// - Getting Started       https://dearimgui.com/getting-started
// - Homepage              https://github.com/ocornut/imgui
// - Releases & changelog  https://github.com/ocornut/imgui/releases
// - Gallery               https://github.com/ocornut/imgui/issues/6897 (please post your screenshots/video there!)
// - Wiki                  https://github.com/ocornut/imgui/wiki (lots of good stuff there)
// - Glossary              https://github.com/ocornut/imgui/wiki/Glossary
// - Issues & support      https://github.com/ocornut/imgui/issues
// - Tests & Automation    https://github.com/ocornut/imgui_test_engine

// For first-time users having issues compiling/linking/running/loading fonts:
// please post in https://github.com/ocornut/imgui/discussions if you cannot find a solution in resources above.
// Everything else should be asked in 'Issues'! We are building a database of cross-linked knowledge there.

// Copyright (c) 2014-2023 Omar Cornut
// Developed by Omar Cornut and every direct or indirect contributors to the GitHub.
// See LICENSE.txt for copyright and licensing details (standard MIT License).
// This library is free but needs your support to sustain development and maintenance.
// Businesses: you can support continued development via B2B invoiced technical support, maintenance and sponsoring contracts.
// PLEASE reach out at omar AT dearimgui DOT com. See https://github.com/ocornut/imgui/wiki/Sponsors
// Businesses: you can also purchase licenses for the Dear ImGui Automation/Test Engine.

// It is recommended that you don't modify imgui.cpp! It will become difficult for you to update the library.
// Note that 'ImGui::' being a namespace, you can add functions into the namespace from your own source files, without
// modifying imgui.h or imgui.cpp. You may include imgui_internal.h to access internal data structures, but it doesn't
// come with any guarantee of forward compatibility. Discussing your changes on the GitHub Issue Tracker may lead you
// to a better solution or official support for them.

/*

Index of this file:

DOCUMENTATION

- MISSION STATEMENT
- CONTROLS GUIDE
- PROGRAMMER GUIDE
  - READ FIRST
  - HOW TO UPDATE TO A NEWER VERSION OF DEAR IMGUI
  - GETTING STARTED WITH INTEGRATING DEAR IMGUI IN YOUR CODE/ENGINE
  - HOW A SIMPLE APPLICATION MAY LOOK LIKE
  - HOW A SIMPLE RENDERING FUNCTION MAY LOOK LIKE
- API BREAKING CHANGES (read me when you update!)
- FREQUENTLY ASKED QUESTIONS (FAQ)
  - Read all answers online: https://www.dearimgui.com/faq, or in docs/FAQ.md (with a Markdown viewer)

CODE
(search for "[SECTION]" in the code to find them)

// [SECTION] INCLUDES
// [SECTION] FORWARD DECLARATIONS
// [SECTION] CONTEXT AND MEMORY ALLOCATORS
// [SECTION] USER FACING STRUCTURES (ImGuiStyle, ImGuiIO)
// [SECTION] MISC HELPERS/UTILITIES (Geometry functions)
// [SECTION] MISC HELPERS/UTILITIES (String, Format, Hash functions)
// [SECTION] MISC HELPERS/UTILITIES (File functions)
// [SECTION] MISC HELPERS/UTILITIES (ImText* functions)
// [SECTION] MISC HELPERS/UTILITIES (Color functions)
// [SECTION] ImGuiStorage
// [SECTION] ImGuiTextFilter
// [SECTION] ImGuiTextBuffer, ImGuiTextIndex
// [SECTION] ImGuiListClipper
// [SECTION] STYLING
// [SECTION] RENDER HELPERS
// [SECTION] INITIALIZATION, SHUTDOWN
// [SECTION] MAIN CODE (most of the code! lots of stuff, needs tidying up!)
// [SECTION] INPUTS
// [SECTION] ERROR CHECKING
// [SECTION] LAYOUT
// [SECTION] SCROLLING
// [SECTION] TOOLTIPS
// [SECTION] POPUPS
// [SECTION] KEYBOARD/GAMEPAD NAVIGATION
// [SECTION] DRAG AND DROP
// [SECTION] LOGGING/CAPTURING
// [SECTION] SETTINGS
// [SECTION] LOCALIZATION
// [SECTION] VIEWPORTS, PLATFORM WINDOWS
// [SECTION] DOCKING
// [SECTION] PLATFORM DEPENDENT HELPERS
// [SECTION] METRICS/DEBUGGER WINDOW
// [SECTION] DEBUG LOG WINDOW
// [SECTION] OTHER DEBUG TOOLS (ITEM PICKER, ID STACK TOOL)

*/

//-----------------------------------------------------------------------------
// DOCUMENTATION
//-----------------------------------------------------------------------------

/*

 MISSION STATEMENT
 =================

 - Easy to use to create code-driven and data-driven tools.
 - Easy to use to create ad hoc short-lived tools and long-lived, more elaborate tools.
 - Easy to hack and improve.
 - Minimize setup and maintenance.
 - Minimize state storage on user side.
 - Minimize state synchronization.
 - Portable, minimize dependencies, run on target (consoles, phones, etc.).
 - Efficient runtime and memory consumption.

 Designed primarily for developers and content-creators, not the typical end-user!
 Some of the current weaknesses (which we aim to address in the future) includes:

 - Doesn't look fancy.
 - Limited layout features, intricate layouts are typically crafted in code.


 CONTROLS GUIDE
 ==============

 - MOUSE CONTROLS
   - Mouse wheel:                   Scroll vertically.
   - SHIFT+Mouse wheel:             Scroll horizontally.
   - Click [X]:                     Close a window, available when 'bool* p_open' is passed to ImGui::Begin().
   - Click ^, Double-Click title:   Collapse window.
   - Drag on corner/border:         Resize window (double-click to auto fit window to its contents).
   - Drag on any empty space:       Move window (unless io.ConfigWindowsMoveFromTitleBarOnly = true).
   - Left-click outside popup:      Close popup stack (right-click over underlying popup: Partially close popup stack).

 - TEXT EDITOR
   - Hold SHIFT or Drag Mouse:      Select text.
   - CTRL+Left/Right:               Word jump.
   - CTRL+Shift+Left/Right:         Select words.
   - CTRL+A or Double-Click:        Select All.
   - CTRL+X, CTRL+C, CTRL+V:        Use OS clipboard.
   - CTRL+Z, CTRL+Y:                Undo, Redo.
   - ESCAPE:                        Revert text to its original value.
   - On OSX, controls are automatically adjusted to match standard OSX text editing shortcuts and behaviors.

 - KEYBOARD CONTROLS
   - Basic:
     - Tab, SHIFT+Tab               Cycle through text editable fields.
     - CTRL+Tab, CTRL+Shift+Tab     Cycle through windows.
     - CTRL+Click                   Input text into a Slider or Drag widget.
   - Extended features with `io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard`:
     - Tab, SHIFT+Tab:              Cycle through every items.
     - Arrow keys                   Move through items using directional navigation. Tweak value.
     - Arrow keys + Alt, Shift      Tweak slower, tweak faster (when using arrow keys).
     - Enter                        Activate item (prefer text input when possible).
     - Space                        Activate item (prefer tweaking with arrows when possible).
     - Escape                       Deactivate item, leave child window, close popup.
     - Page Up, Page Down           Previous page, next page.
     - Home, End                    Scroll to top, scroll to bottom.
     - Alt                          Toggle between scrolling layer and menu layer.
     - CTRL+Tab then Ctrl+Arrows    Move window. Hold SHIFT to resize instead of moving.
   - Output when ImGuiConfigFlags_NavEnableKeyboard set,
     - io.WantCaptureKeyboard flag is set when keyboard is claimed.
     - io.NavActive: true when a window is focused and it doesn't have the ImGuiWindowFlags_NoNavInputs flag set.
     - io.NavVisible: true when the navigation cursor is visible (usually goes to back false when mouse is used).

 - GAMEPAD CONTROLS
   - Enable with 'io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad'.
   - Particularly useful to use Dear ImGui on a console system (e.g. PlayStation, Switch, Xbox) without a mouse!
   - Download controller mapping PNG/PSD at http://dearimgui.com/controls_sheets
   - Backend support: backend needs to:
      - Set 'io.BackendFlags |= ImGuiBackendFlags_HasGamepad' + call io.AddKeyEvent/AddKeyAnalogEvent() with ImGuiKey_Gamepad_XXX keys.
      - For analog values (0.0f to 1.0f), backend is responsible to handling a dead-zone and rescaling inputs accordingly.
        Backend code will probably need to transform your raw inputs (such as e.g. remapping your 0.2..0.9 raw input range to 0.0..1.0 imgui range, etc.).
      - BEFORE 1.87, BACKENDS USED TO WRITE TO io.NavInputs[]. This is now obsolete. Please call io functions instead!
   - If you need to share inputs between your game and the Dear ImGui interface, the easiest approach is to go all-or-nothing,
     with a buttons combo to toggle the target. Please reach out if you think the game vs navigation input sharing could be improved.

 - REMOTE INPUTS SHARING & MOUSE EMULATION
   - PS4/PS5 users: Consider emulating a mouse cursor with DualShock touch pad or a spare analog stick as a mouse-emulation fallback.
   - Consoles/Tablet/Phone users: Consider using a Synergy 1.x server (on your PC) + run examples/libs/synergy/uSynergy.c (on your console/tablet/phone app)
     in order to share your PC mouse/keyboard.
   - See https://github.com/ocornut/imgui/wiki/Useful-Extensions#remoting for other remoting solutions.
   - On a TV/console system where readability may be lower or mouse inputs may be awkward, you may want to set the ImGuiConfigFlags_NavEnableSetMousePos flag.
     Enabling ImGuiConfigFlags_NavEnableSetMousePos + ImGuiBackendFlags_HasSetMousePos instructs Dear ImGui to move your mouse cursor along with navigation movements.
     When enabled, the NewFrame() function may alter 'io.MousePos' and set 'io.WantSetMousePos' to notify you that it wants the mouse cursor to be moved.
     When that happens your backend NEEDS to move the OS or underlying mouse cursor on the next frame. Some of the backends in examples/ do that.
     (If you set the NavEnableSetMousePos flag but don't honor 'io.WantSetMousePos' properly, Dear ImGui will misbehave as it will see your mouse moving back & forth!)
     (In a setup when you may not have easy control over the mouse cursor, e.g. uSynergy.c doesn't expose moving remote mouse cursor, you may want
     to set a boolean to ignore your other external mouse positions until the external source is moved again.)


 PROGRAMMER GUIDE
 ================

 READ FIRST
 ----------
 - Remember to check the wonderful Wiki (https://github.com/ocornut/imgui/wiki)
 - Your code creates the UI every frame of your application loop, if your code doesn't run the UI is gone!
   The UI can be highly dynamic, there are no construction or destruction steps, less superfluous
   data retention on your side, less state duplication, less state synchronization, fewer bugs.
 - Call and read ImGui::ShowDemoWindow() for demo code demonstrating most features.
   Or browse https://pthom.github.io/imgui_manual_online/manual/imgui_manual.html for interactive web version.
 - The library is designed to be built from sources. Avoid pre-compiled binaries and packaged versions. See imconfig.h to configure your build.
 - Dear ImGui is an implementation of the IMGUI paradigm (immediate-mode graphical user interface, a term coined by Casey Muratori).
   You can learn about IMGUI principles at http://www.johno.se/book/imgui.html, http://mollyrocket.com/861 & more links in Wiki.
 - Dear ImGui is a "single pass" rasterizing implementation of the IMGUI paradigm, aimed at ease of use and high-performances.
   For every application frame, your UI code will be called only once. This is in contrast to e.g. Unity's implementation of an IMGUI,
   where the UI code is called multiple times ("multiple passes") from a single entry point. There are pros and cons to both approaches.
 - Our origin is on the top-left. In axis aligned bounding boxes, Min = top-left, Max = bottom-right.
 - Please make sure you have asserts enabled (IM_ASSERT redirects to assert() by default, but can be redirected).
   If you get an assert, read the messages and comments around the assert.
 - This codebase aims to be highly optimized:
   - A typical idle frame should never call malloc/free.
   - We rely on a maximum of constant-time or O(N) algorithms. Limiting searches/scans as much as possible.
   - We put particular energy in making sure performances are decent with typical "Debug" build settings as well.
     Which mean we tend to avoid over-relying on "zero-cost abstraction" as they aren't zero-cost at all.
 - This codebase aims to be both highly opinionated and highly flexible:
   - This code works because of the things it choose to solve or not solve.
   - C++: this is a pragmatic C-ish codebase: we don't use fancy C++ features, we don't include C++ headers,
     and ImGui:: is a namespace. We rarely use member functions (and when we did, I am mostly regretting it now).
     This is to increase compatibility, increase maintainability and facilitate use from other languages.
   - C++: ImVec2/ImVec4 do not expose math operators by default, because it is expected that you use your own math types.
     See FAQ "How can I use my own math types instead of ImVec2/ImVec4?" for details about setting up imconfig.h for that.
     We can can optionally export math operators for ImVec2/ImVec4 using IMGUI_DEFINE_MATH_OPERATORS, which we use internally.
   - C++: pay attention that ImVector<> manipulates plain-old-data and does not honor construction/destruction
     (so don't use ImVector in your code or at our own risk!).
   - Building: We don't use nor mandate a build system for the main library.
     This is in an effort to ensure that it works in the real world aka with any esoteric build setup.
     This is also because providing a build system for the main library would be of little-value.
     The build problems are almost never coming from the main library but from specific backends.


 HOW TO UPDATE TO A NEWER VERSION OF DEAR IMGUI
 ----------------------------------------------
 - Update submodule or copy/overwrite every file.
 - About imconfig.h:
   - You may modify your copy of imconfig.h, in this case don't overwrite it.
   - or you may locally branch to modify imconfig.h and merge/rebase latest.
   - or you may '#define IMGUI_USER_CONFIG "my_config_file.h"' globally from your build system to
     specify a custom path for your imconfig.h file and instead not have to modify the default one.

 - Overwrite all the sources files except for imconfig.h (if you have modified your copy of imconfig.h)
 - Or maintain your own branch where you have imconfig.h modified as a top-most commit which you can regularly rebase over "master".
 - You can also use '#define IMGUI_USER_CONFIG "my_config_file.h" to redirect configuration to your own file.
 - Read the "API BREAKING CHANGES" section (below). This is where we list occasional API breaking changes.
   If a function/type has been renamed / or marked obsolete, try to fix the name in your code before it is permanently removed
   from the public API. If you have a problem with a missing function/symbols, search for its name in the code, there will
   likely be a comment about it. Please report any issue to the GitHub page!
 - To find out usage of old API, you can add '#define IMGUI_DISABLE_OBSOLETE_FUNCTIONS' in your configuration file.
 - Try to keep your copy of Dear ImGui reasonably up to date!


 GETTING STARTED WITH INTEGRATING DEAR IMGUI IN YOUR CODE/ENGINE
 ---------------------------------------------------------------
 - See https://github.com/ocornut/imgui/wiki/Getting-Started.
 - Run and study the examples and demo in imgui_demo.cpp to get acquainted with the library.
 - In the majority of cases you should be able to use unmodified backends files available in the backends/ folder.
 - Add the Dear ImGui source files + selected backend source files to your projects or using your preferred build system.
   It is recommended you build and statically link the .cpp files as part of your project and NOT as a shared library (DLL).
 - You can later customize the imconfig.h file to tweak some compile-time behavior, such as integrating Dear ImGui types with your own maths types.
 - When using Dear ImGui, your programming IDE is your friend: follow the declaration of variables, functions and types to find comments about them.
 - Dear ImGui never touches or knows about your GPU state. The only function that knows about GPU is the draw function that you provide.
   Effectively it means you can create widgets at any time in your code, regardless of considerations of being in "update" vs "render"
   phases of your own application. All rendering information is stored into command-lists that you will retrieve after calling ImGui::Render().
 - Refer to the backends and demo applications in the examples/ folder for instruction on how to setup your code.
 - If you are running over a standard OS with a common graphics API, you should be able to use unmodified imgui_impl_*** files from the examples/ folder.


 HOW A SIMPLE APPLICATION MAY LOOK LIKE
 --------------------------------------
 EXHIBIT 1: USING THE EXAMPLE BACKENDS (= imgui_impl_XXX.cpp files from the backends/ folder).
 The sub-folders in examples/ contain examples applications following this structure.

     // Application init: create a dear imgui context, setup some options, load fonts
     ImGui::CreateContext();
     ImGuiIO& io = ImGui::GetIO();
     // TODO: Set optional io.ConfigFlags values, e.g. 'io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard' to enable keyboard controls.
     // TODO: Fill optional fields of the io structure later.
     // TODO: Load TTF/OTF fonts if you don't want to use the default font.

     // Initialize helper Platform and Renderer backends (here we are using imgui_impl_win32.cpp and imgui_impl_dx11.cpp)
     ImGui_ImplWin32_Init(hwnd);
     ImGui_ImplDX11_Init(g_pd3dDevice, g_pd3dDeviceContext);

     // Application main loop
     while (true)
     {
         // Feed inputs to dear imgui, start new frame
         ImGui_ImplDX11_NewFrame();
         ImGui_ImplWin32_NewFrame();
         ImGui::NewFrame();

         // Any application code here
         ImGui::Text("Hello, world!");

         // Render dear imgui into screen
         ImGui::Render();
         ImGui_ImplDX11_RenderDrawData(ImGui::GetDrawData());
         g_pSwapChain->Present(1, 0);
     }

     // Shutdown
     ImGui_ImplDX11_Shutdown();
     ImGui_ImplWin32_Shutdown();
     ImGui::DestroyContext();

 EXHIBIT 2: IMPLEMENTING CUSTOM BACKEND / CUSTOM ENGINE

     // Application init: create a dear imgui context, setup some options, load fonts
     ImGui::CreateContext();
     ImGuiIO& io = ImGui::GetIO();
     // TODO: Set optional io.ConfigFlags values, e.g. 'io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard' to enable keyboard controls.
     // TODO: Fill optional fields of the io structure later.
     // TODO: Load TTF/OTF fonts if you don't want to use the default font.

     // Build and load the texture atlas into a texture
     // (In the examples/ app this is usually done within the ImGui_ImplXXX_Init() function from one of the demo Renderer)
     int width, height;
     unsigned char* pixels = nullptr;
     io.Fonts->GetTexDataAsRGBA32(&pixels, &width, &height);

     // At this point you've got the texture data and you need to upload that to your graphic system:
     // After we have created the texture, store its pointer/identifier (_in whichever format your engine uses_) in 'io.Fonts->TexID'.
     // This will be passed back to your via the renderer. Basically ImTextureID == void*. Read FAQ for details about ImTextureID.
     MyTexture* texture = MyEngine::CreateTextureFromMemoryPixels(pixels, width, height, TEXTURE_TYPE_RGBA32)
     io.Fonts->SetTexID((void*)texture);

     // Application main loop
     while (true)
     {
        // Setup low-level inputs, e.g. on Win32: calling GetKeyboardState(), or write to those fields from your Windows message handlers, etc.
        // (In the examples/ app this is usually done within the ImGui_ImplXXX_NewFrame() function from one of the demo Platform Backends)
        io.DeltaTime = 1.0f/60.0f;              // set the time elapsed since the previous frame (in seconds)
        io.DisplaySize.x = 1920.0f;             // set the current display width
        io.DisplaySize.y = 1280.0f;             // set the current display height here
        io.AddMousePosEvent(mouse_x, mouse_y);  // update mouse position
        io.AddMouseButtonEvent(0, mouse_b[0]);  // update mouse button states
        io.AddMouseButtonEvent(1, mouse_b[1]);  // update mouse button states

        // Call NewFrame(), after this point you can use ImGui::* functions anytime
        // (So you want to try calling NewFrame() as early as you can in your main loop to be able to use Dear ImGui everywhere)
        ImGui::NewFrame();

        // Most of your application code here
        ImGui::Text("Hello, world!");
        MyGameUpdate(); // may use any Dear ImGui functions, e.g. ImGui::Begin("My window"); ImGui::Text("Hello, world!"); ImGui::End();
        MyGameRender(); // may use any Dear ImGui functions as well!

        // Render dear imgui, swap buffers
        // (You want to try calling EndFrame/Render as late as you can, to be able to use Dear ImGui in your own game rendering code)
        ImGui::EndFrame();
        ImGui::Render();
        ImDrawData* draw_data = ImGui::GetDrawData();
        MyImGuiRenderFunction(draw_data);
        SwapBuffers();
     }

     // Shutdown
     ImGui::DestroyContext();

 To decide whether to dispatch mouse/keyboard inputs to Dear ImGui to the rest of your application,
 you should read the 'io.WantCaptureMouse', 'io.WantCaptureKeyboard' and 'io.WantTextInput' flags!
 Please read the FAQ and example applications for details about this!


 HOW A SIMPLE RENDERING FUNCTION MAY LOOK LIKE
 ---------------------------------------------
 The backends in impl_impl_XXX.cpp files contain many working implementations of a rendering function.

    void MyImGuiRenderFunction(ImDrawData* draw_data)
    {
       // TODO: Setup render state: alpha-blending enabled, no face culling, no depth testing, scissor enabled
       // TODO: Setup texture sampling state: sample with bilinear filtering (NOT point/nearest filtering). Use 'io.Fonts->Flags |= ImFontAtlasFlags_NoBakedLines;' to allow point/nearest filtering.
       // TODO: Setup viewport covering draw_data->DisplayPos to draw_data->DisplayPos + draw_data->DisplaySize
       // TODO: Setup orthographic projection matrix cover draw_data->DisplayPos to draw_data->DisplayPos + draw_data->DisplaySize
       // TODO: Setup shader: vertex { float2 pos, float2 uv, u32 color }, fragment shader sample color from 1 texture, multiply by vertex color.
       ImVec2 clip_off = draw_data->DisplayPos;
       for (int n = 0; n < draw_data->CmdListsCount; n++)
       {
          const ImDrawList* cmd_list = draw_data->CmdLists[n];
          const ImDrawVert* vtx_buffer = cmd_list->VtxBuffer.Data;  // vertex buffer generated by Dear ImGui
          const ImDrawIdx* idx_buffer = cmd_list->IdxBuffer.Data;   // index buffer generated by Dear ImGui
          for (int cmd_i = 0; cmd_i < cmd_list->CmdBuffer.Size; cmd_i++)
          {
             const ImDrawCmd* pcmd = &cmd_list->CmdBuffer[cmd_i];
             if (pcmd->UserCallback)
             {
                 pcmd->UserCallback(cmd_list, pcmd);
             }
             else
             {
                 // Project scissor/clipping rectangles into framebuffer space
                 ImVec2 clip_min(pcmd->ClipRect.x - clip_off.x, pcmd->ClipRect.y - clip_off.y);
                 ImVec2 clip_max(pcmd->ClipRect.z - clip_off.x, pcmd->ClipRect.w - clip_off.y);
                 if (clip_max.x <= clip_min.x || clip_max.y <= clip_min.y)
                     continue;

                 // We are using scissoring to clip some objects. All low-level graphics API should support it.
                 // - If your engine doesn't support scissoring yet, you may ignore this at first. You will get some small glitches
                 //   (some elements visible outside their bounds) but you can fix that once everything else works!
                 // - Clipping coordinates are provided in imgui coordinates space:
                 //   - For a given viewport, draw_data->DisplayPos == viewport->Pos and draw_data->DisplaySize == viewport->Size
                 //   - In a single viewport application, draw_data->DisplayPos == (0,0) and draw_data->DisplaySize == io.DisplaySize, but always use GetMainViewport()->Pos/Size instead of hardcoding those values.
                 //   - In the interest of supporting multi-viewport applications (see 'docking' branch on github),
                 //     always subtract draw_data->DisplayPos from clipping bounds to convert them to your viewport space.
                 // - Note that pcmd->ClipRect contains Min+Max bounds. Some graphics API may use Min+Max, other may use Min+Size (size being Max-Min)
                 MyEngineSetScissor(clip_min.x, clip_min.y, clip_max.x, clip_max.y);

                 // The texture for the draw call is specified by pcmd->GetTexID().
                 // The vast majority of draw calls will use the Dear ImGui texture atlas, which value you have set yourself during initialization.
                 MyEngineBindTexture((MyTexture*)pcmd->GetTexID());

                 // Render 'pcmd->ElemCount/3' indexed triangles.
                 // By default the indices ImDrawIdx are 16-bit, you can change them to 32-bit in imconfig.h if your engine doesn't support 16-bit indices.
                 MyEngineDrawIndexedTriangles(pcmd->ElemCount, sizeof(ImDrawIdx) == 2 ? GL_UNSIGNED_SHORT : GL_UNSIGNED_INT, idx_buffer + pcmd->IdxOffset, vtx_buffer, pcmd->VtxOffset);
             }
          }
       }
    }


 API BREAKING CHANGES
 ====================

 Occasionally introducing changes that are breaking the API. We try to make the breakage minor and easy to fix.
 Below is a change-log of API breaking changes only. If you are using one of the functions listed, expect to have to fix some code.
 When you are not sure about an old symbol or function name, try using the Search/Find function of your IDE to look for comments or references in all imgui files.
 You can read releases logs https://github.com/ocornut/imgui/releases for more details.

(Docking/Viewport Branch)
 - 2023/XX/XX (1.XXXX) - when multi-viewports are enabled, all positions will be in your natural OS coordinates space. It means that:
                          - reference to hard-coded positions such as in SetNextWindowPos(ImVec2(0,0)) are probably not what you want anymore.
                            you may use GetMainViewport()->Pos to offset hard-coded positions, e.g. SetNextWindowPos(GetMainViewport()->Pos)
                          - likewise io.MousePos and GetMousePos() will use OS coordinates.
                            If you query mouse positions to interact with non-imgui coordinates you will need to offset them, e.g. subtract GetWindowViewport()->Pos.

 - 2023/11/09 (1.90.0) - removed IM_OFFSETOF() macro in favor of using offsetof() available in C++11. Kept redirection define (will obsolete).
 - 2023/11/07 (1.90.0) - removed BeginChildFrame()/EndChildFrame() in favor of using BeginChild() with the ImGuiChildFlags_FrameStyle flag. kept inline redirection function (will obsolete).
                         those functions were merely PushStyle/PopStyle helpers, the removal isn't so much motivated by needing to add the feature in BeginChild(), but by the necessity to avoid BeginChildFrame() signature mismatching BeginChild() signature and features.
 - 2023/11/02 (1.90.0) - BeginChild: upgraded 'bool border = true' parameter to 'ImGuiChildFlags flags' type, added ImGuiChildFlags_Border equivalent. As with our prior "bool-to-flags" API updates, the ImGuiChildFlags_Border value is guaranteed to be == true forever to ensure a smoother transition, meaning all existing calls will still work.
                           - old: BeginChild("Name", size, true)
                           - new: BeginChild("Name", size, ImGuiChildFlags_Border)
                           - old: BeginChild("Name", size, false)
                           - new: BeginChild("Name", size) or BeginChild("Name", 0) or BeginChild("Name", size, ImGuiChildFlags_None)
 - 2023/11/02 (1.90.0) - BeginChild: added child-flag ImGuiChildFlags_AlwaysUseWindowPadding as a replacement for the window-flag ImGuiWindowFlags_AlwaysUseWindowPadding: the feature only ever made sense for BeginChild() anyhow.
                           - old: BeginChild("Name", size, 0, ImGuiWindowFlags_AlwaysUseWindowPadding);
                           - new: BeginChild("Name", size, ImGuiChildFlags_AlwaysUseWindowPadding, 0);
 - 2023/09/27 (1.90.0) - io: removed io.MetricsActiveAllocations introduced in 1.63. Same as 'g.DebugMemAllocCount - g.DebugMemFreeCount' (still displayed in Metrics, unlikely to be accessed by end-user).
 - 2023/09/26 (1.90.0) - debug tools: Renamed ShowStackToolWindow() ("Stack Tool") to ShowIDStackToolWindow() ("ID Stack Tool"), as earlier name was misleading. Kept inline redirection function. (#4631)
 - 2023/09/15 (1.90.0) - ListBox, Combo: changed signature of "name getter" callback in old one-liner ListBox()/Combo() apis. kept inline redirection function (will obsolete).
                           - old: bool Combo(const char* label, int* current_item, bool (*getter)(void* user_data, int idx, const char** out_text), ...)
                           - new: bool Combo(const char* label, int* current_item, const char* (*getter)(void* user_data, int idx), ...);
                           - old: bool ListBox(const char* label, int* current_item, bool (*getting)(void* user_data, int idx, const char** out_text), ...);
                           - new: bool ListBox(const char* label, int* current_item, const char* (*getter)(void* user_data, int idx), ...);
 - 2023/09/08 (1.90.0) - commented out obsolete redirecting functions:
                           - GetWindowContentRegionWidth()  -> use GetWindowContentRegionMax().x - GetWindowContentRegionMin().x. Consider that generally 'GetContentRegionAvail().x' is more useful.
                           - ImDrawCornerFlags_XXX          -> use ImDrawFlags_RoundCornersXXX flags. Read 1.82 Changelog for details + grep commented names in sources.
                       - commented out runtime support for hardcoded ~0 or 0x01..0x0F rounding flags values for AddRect()/AddRectFilled()/PathRect()/AddImageRounded() -> use ImDrawFlags_RoundCornersXXX flags. Read 1.82 Changelog for details
 - 2023/08/25 (1.89.9) - clipper: Renamed IncludeRangeByIndices() (also called ForceDisplayRangeByIndices() before 1.89.6) to IncludeItemsByIndex(). Kept inline redirection function. Sorry!
 - 2023/07/12 (1.89.8) - ImDrawData: CmdLists now owned, changed from ImDrawList** to ImVector<ImDrawList*>. Majority of users shouldn't be affected, but you cannot compare to NULL nor reassign manually anymore. Instead use AddDrawList(). (#6406, #4879, #1878)
 - 2023/06/28 (1.89.7) - overlapping items: obsoleted 'SetItemAllowOverlap()' (called after item) in favor of calling 'SetNextItemAllowOverlap()' (called before item). 'SetItemAllowOverlap()' didn't and couldn't work reliably since 1.89 (2022-11-15).
 - 2023/06/28 (1.89.7) - overlapping items: renamed 'ImGuiTreeNodeFlags_AllowItemOverlap' to 'ImGuiTreeNodeFlags_AllowOverlap', 'ImGuiSelectableFlags_AllowItemOverlap' to 'ImGuiSelectableFlags_AllowOverlap'. Kept redirecting enums (will obsolete).
 - 2023/06/28 (1.89.7) - overlapping items: IsItemHovered() now by default return false when querying an item using AllowOverlap mode which is being overlapped. Use ImGuiHoveredFlags_AllowWhenOverlappedByItem to revert to old behavior.
 - 2023/06/28 (1.89.7) - overlapping items: Selectable and TreeNode don't allow overlap when active so overlapping widgets won't appear as hovered. While this fixes a common small visual issue, it also means that calling IsItemHovered() after a non-reactive elements - e.g. Text() - overlapping an active one may fail if you don't use IsItemHovered(ImGuiHoveredFlags_AllowWhenBlockedByActiveItem). (#6610)
 - 2023/06/20 (1.89.7) - moved io.HoverDelayShort/io.HoverDelayNormal to style.HoverDelayShort/style.HoverDelayNormal. As the fields were added in 1.89 and expected to be left unchanged by most users, or only tweaked once during app initialization, we are exceptionally accepting the breakage.
 - 2023/05/30 (1.89.6) - backends: renamed "imgui_impl_sdlrenderer.cpp" to "imgui_impl_sdlrenderer2.cpp" and "imgui_impl_sdlrenderer.h" to "imgui_impl_sdlrenderer2.h". This is in prevision for the future release of SDL3.
 - 2023/05/22 (1.89.6) - listbox: commented out obsolete/redirecting functions that were marked obsolete more than two years ago:
                           - ListBoxHeader()  -> use BeginListBox() (note how two variants of ListBoxHeader() existed. Check commented versions in imgui.h for reference)
                           - ListBoxFooter()  -> use EndListBox()
 - 2023/05/15 (1.89.6) - clipper: commented out obsolete redirection constructor 'ImGuiListClipper(int items_count, float items_height = -1.0f)' that was marked obsolete in 1.79. Use default constructor + clipper.Begin().
 - 2023/05/15 (1.89.6) - clipper: renamed ImGuiListClipper::ForceDisplayRangeByIndices() to ImGuiListClipper::IncludeRangeByIndices().
 - 2023/03/14 (1.89.4) - commented out redirecting enums/functions names that were marked obsolete two years ago:
                           - ImGuiSliderFlags_ClampOnInput        -> use ImGuiSliderFlags_AlwaysClamp
                           - ImGuiInputTextFlags_AlwaysInsertMode -> use ImGuiInputTextFlags_AlwaysOverwrite
                           - ImDrawList::AddBezierCurve()         -> use ImDrawList::AddBezierCubic()
                           - ImDrawList::PathBezierCurveTo()      -> use ImDrawList::PathBezierCubicCurveTo()
 - 2023/03/09 (1.89.4) - renamed PushAllowKeyboardFocus()/PopAllowKeyboardFocus() to PushTabStop()/PopTabStop(). Kept inline redirection functions (will obsolete).
 - 2023/03/09 (1.89.4) - tooltips: Added 'bool' return value to BeginTooltip() for API consistency. Please only submit contents and call EndTooltip() if BeginTooltip() returns true. In reality the function will _currently_ always return true, but further changes down the line may change this, best to clarify API sooner.
 - 2023/02/15 (1.89.4) - moved the optional "courtesy maths operators" implementation from imgui_internal.h in imgui.h.
                         Even though we encourage using your own maths types and operators by setting up IM_VEC2_CLASS_EXTRA,
                         it has been frequently requested by people to use our own. We had an opt-in define which was
                         previously fulfilled in imgui_internal.h. It is now fulfilled in imgui.h. (#6164)
                           - OK:     #define IMGUI_DEFINE_MATH_OPERATORS / #include "imgui.h" / #include "imgui_internal.h"
                           - Error:  #include "imgui.h" / #define IMGUI_DEFINE_MATH_OPERATORS / #include "imgui_internal.h"
 - 2023/02/07 (1.89.3) - backends: renamed "imgui_impl_sdl.cpp" to "imgui_impl_sdl2.cpp" and "imgui_impl_sdl.h" to "imgui_impl_sdl2.h". (#6146) This is in prevision for the future release of SDL3.
 - 2022/10/26 (1.89)   - commented out redirecting OpenPopupContextItem() which was briefly the name of OpenPopupOnItemClick() from 1.77 to 1.79.
 - 2022/10/12 (1.89)   - removed runtime patching of invalid "%f"/"%0.f" format strings for DragInt()/SliderInt(). This was obsoleted in 1.61 (May 2018). See 1.61 changelog for details.
 - 2022/09/26 (1.89)   - renamed and merged keyboard modifiers key enums and flags into a same set. Kept inline redirection enums (will obsolete).
                           - ImGuiKey_ModCtrl  and ImGuiModFlags_Ctrl  -> ImGuiMod_Ctrl
                           - ImGuiKey_ModShift and ImGuiModFlags_Shift -> ImGuiMod_Shift
                           - ImGuiKey_ModAlt   and ImGuiModFlags_Alt   -> ImGuiMod_Alt
                           - ImGuiKey_ModSuper and ImGuiModFlags_Super -> ImGuiMod_Super
                         the ImGuiKey_ModXXX were introduced in 1.87 and mostly used by backends.
                         the ImGuiModFlags_XXX have been exposed in imgui.h but not really used by any public api only by third-party extensions.
                         exceptionally commenting out the older ImGuiKeyModFlags_XXX names ahead of obsolescence schedule to reduce confusion and because they were not meant to be used anyway.
 - 2022/09/20 (1.89)   - ImGuiKey is now a typed enum, allowing ImGuiKey_XXX symbols to be named in debuggers.
                         this will require uses of legacy backend-dependent indices to be casted, e.g.
                            - with imgui_impl_glfw:  IsKeyPressed(GLFW_KEY_A) -> IsKeyPressed((ImGuiKey)GLFW_KEY_A);
                            - with imgui_impl_win32: IsKeyPressed('A')        -> IsKeyPressed((ImGuiKey)'A')
                            - etc. However if you are upgrading code you might well use the better, backend-agnostic IsKeyPressed(ImGuiKey_A) now!
 - 2022/09/12 (1.89) - removed the bizarre legacy default argument for 'TreePush(const void* ptr = NULL)', always pass a pointer value explicitly. NULL/nullptr is ok but require cast, e.g. TreePush((void*)nullptr);
 - 2022/09/05 (1.89) - commented out redirecting functions/enums names that were marked obsolete in 1.77 and 1.78 (June 2020):
                         - DragScalar(), DragScalarN(), DragFloat(), DragFloat2(), DragFloat3(), DragFloat4(): For old signatures ending with (..., const char* format, float power = 1.0f) -> use (..., format ImGuiSliderFlags_Logarithmic) if power != 1.0f.
                         - SliderScalar(), SliderScalarN(), SliderFloat(), SliderFloat2(), SliderFloat3(), SliderFloat4(): For old signatures ending with (..., const char* format, float power = 1.0f) -> use (..., format ImGuiSliderFlags_Logarithmic) if power != 1.0f.
                         - BeginPopupContextWindow(const char*, ImGuiMouseButton, bool) -> use BeginPopupContextWindow(const char*, ImGuiPopupFlags)
 - 2022/09/02 (1.89) - obsoleted using SetCursorPos()/SetCursorScreenPos() to extend parent window/cell boundaries.
                       this relates to when moving the cursor position beyond current boundaries WITHOUT submitting an item.
                         - previously this would make the window content size ~200x200:
                              Begin(...) + SetCursorScreenPos(GetCursorScreenPos() + ImVec2(200,200)) + End();
                         - instead, please submit an item:
                              Begin(...) + SetCursorScreenPos(GetCursorScreenPos() + ImVec2(200,200)) + Dummy(ImVec2(0,0)) + End();
                         - alternative:
                              Begin(...) + Dummy(ImVec2(200,200)) + End();
                         - content size is now only extended when submitting an item!
                         - with '#define IMGUI_DISABLE_OBSOLETE_FUNCTIONS' this will now be detected and assert.
                         - without '#define IMGUI_DISABLE_OBSOLETE_FUNCTIONS' this will silently be fixed until we obsolete it.
 - 2022/08/03 (1.89) - changed signature of ImageButton() function. Kept redirection function (will obsolete).
                        - added 'const char* str_id' parameter + removed 'int frame_padding = -1' parameter.
                        - old signature: bool ImageButton(ImTextureID tex_id, ImVec2 size, ImVec2 uv0 = ImVec2(0,0), ImVec2 uv1 = ImVec2(1,1), int frame_padding = -1, ImVec4 bg_col = ImVec4(0,0,0,0), ImVec4 tint_col = ImVec4(1,1,1,1));
                          - used the ImTextureID value to create an ID. This was inconsistent with other functions, led to ID conflicts, and caused problems with engines using transient ImTextureID values.
                          - had a FramePadding override which was inconsistent with other functions and made the already-long signature even longer.
                        - new signature: bool ImageButton(const char* str_id, ImTextureID tex_id, ImVec2 size, ImVec2 uv0 = ImVec2(0,0), ImVec2 uv1 = ImVec2(1,1), ImVec4 bg_col = ImVec4(0,0,0,0), ImVec4 tint_col = ImVec4(1,1,1,1));
                          - requires an explicit identifier. You may still use e.g. PushID() calls and then pass an empty identifier.
                          - always uses style.FramePadding for padding, to be consistent with other buttons. You may use PushStyleVar() to alter this.
 - 2022/07/08 (1.89) - inputs: removed io.NavInputs[] and ImGuiNavInput enum (following 1.87 changes).
                        - Official backends from 1.87+                  -> no issue.
                        - Official backends from 1.60 to 1.86           -> will build and convert gamepad inputs, unless IMGUI_DISABLE_OBSOLETE_KEYIO is defined. Need updating!
                        - Custom backends not writing to io.NavInputs[] -> no issue.
                        - Custom backends writing to io.NavInputs[]     -> will build and convert gamepad inputs, unless IMGUI_DISABLE_OBSOLETE_KEYIO is defined. Need fixing!
                        - TL;DR: Backends should call io.AddKeyEvent()/io.AddKeyAnalogEvent() with ImGuiKey_GamepadXXX values instead of filling io.NavInput[].
 - 2022/06/15 (1.88) - renamed IMGUI_DISABLE_METRICS_WINDOW to IMGUI_DISABLE_DEBUG_TOOLS for correctness. kept support for old define (will obsolete).
 - 2022/05/03 (1.88) - backends: osx: removed ImGui_ImplOSX_HandleEvent() from backend API in favor of backend automatically handling event capture. All ImGui_ImplOSX_HandleEvent() calls should be removed as they are now unnecessary.
 - 2022/04/05 (1.88) - inputs: renamed ImGuiKeyModFlags to ImGuiModFlags. Kept inline redirection enums (will obsolete). This was never used in public API functions but technically present in imgui.h and ImGuiIO.
 - 2022/01/20 (1.87) - inputs: reworded gamepad IO.
                        - Backend writing to io.NavInputs[]            -> backend should call io.AddKeyEvent()/io.AddKeyAnalogEvent() with ImGuiKey_GamepadXXX values.
 - 2022/01/19 (1.87) - sliders, drags: removed support for legacy arithmetic operators (+,+-,*,/) when inputing text. This doesn't break any api/code but a feature that used to be accessible by end-users (which seemingly no one used).
 - 2022/01/17 (1.87) - inputs: reworked mouse IO.
                        - Backend writing to io.MousePos               -> backend should call io.AddMousePosEvent()
                        - Backend writing to io.MouseDown[]            -> backend should call io.AddMouseButtonEvent()
                        - Backend writing to io.MouseWheel             -> backend should call io.AddMouseWheelEvent()
                        - Backend writing to io.MouseHoveredViewport   -> backend should call io.AddMouseViewportEvent() [Docking branch w/ multi-viewports only]
                       note: for all calls to IO new functions, the Dear ImGui context should be bound/current.
                       read https://github.com/ocornut/imgui/issues/4921 for details.
 - 2022/01/10 (1.87) - inputs: reworked keyboard IO. Removed io.KeyMap[], io.KeysDown[] in favor of calling io.AddKeyEvent(). Removed GetKeyIndex(), now unecessary. All IsKeyXXX() functions now take ImGuiKey values. All features are still functional until IMGUI_DISABLE_OBSOLETE_KEYIO is defined. Read Changelog and Release Notes for details.
                        - IsKeyPressed(MY_NATIVE_KEY_XXX)              -> use IsKeyPressed(ImGuiKey_XXX)
                        - IsKeyPressed(GetKeyIndex(ImGuiKey_XXX))      -> use IsKeyPressed(ImGuiKey_XXX)
                        - Backend writing to io.KeyMap[],io.KeysDown[] -> backend should call io.AddKeyEvent() (+ call io.SetKeyEventNativeData() if you want legacy user code to stil function with legacy key codes).
                        - Backend writing to io.KeyCtrl, io.KeyShift.. -> backend should call io.AddKeyEvent() with ImGuiMod_XXX values. *IF YOU PULLED CODE BETWEEN 2021/01/10 and 2021/01/27: We used to have a io.AddKeyModsEvent() function which was now replaced by io.AddKeyEvent() with ImGuiMod_XXX values.*
                     - one case won't work with backward compatibility: if your custom backend used ImGuiKey as mock native indices (e.g. "io.KeyMap[ImGuiKey_A] = ImGuiKey_A") because those values are now larger than the legacy KeyDown[] array. Will assert.
                     - inputs: added ImGuiKey_ModCtrl/ImGuiKey_ModShift/ImGuiKey_ModAlt/ImGuiKey_ModSuper values to submit keyboard modifiers using io.AddKeyEvent(), instead of writing directly to io.KeyCtrl, io.KeyShift, io.KeyAlt, io.KeySuper.
 - 2022/01/05 (1.87) - inputs: renamed ImGuiKey_KeyPadEnter to ImGuiKey_KeypadEnter to align with new symbols. Kept redirection enum.
 - 2022/01/05 (1.87) - removed io.ImeSetInputScreenPosFn() in favor of more flexible io.SetPlatformImeDataFn(). Removed 'void* io.ImeWindowHandle' in favor of writing to 'void* ImGuiViewport::PlatformHandleRaw'.
 - 2022/01/01 (1.87) - commented out redirecting functions/enums names that were marked obsolete in 1.69, 1.70, 1.71, 1.72 (March-July 2019)
                        - ImGui::SetNextTreeNodeOpen()        -> use ImGui::SetNextItemOpen()
                        - ImGui::GetContentRegionAvailWidth() -> use ImGui::GetContentRegionAvail().x
                        - ImGui::TreeAdvanceToLabelPos()      -> use ImGui::SetCursorPosX(ImGui::GetCursorPosX() + ImGui::GetTreeNodeToLabelSpacing());
                        - ImFontAtlas::CustomRect             -> use ImFontAtlasCustomRect
                        - ImGuiColorEditFlags_RGB/HSV/HEX     -> use ImGuiColorEditFlags_DisplayRGB/HSV/Hex
 - 2021/12/20 (1.86) - backends: removed obsolete Marmalade backend (imgui_impl_marmalade.cpp) + example. Find last supported version at https://github.com/ocornut/imgui/wiki/Bindings
 - 2021/11/04 (1.86) - removed CalcListClipping() function. Prefer using ImGuiListClipper which can return non-contiguous ranges. Please open an issue if you think you really need this function.
 - 2021/08/23 (1.85) - removed GetWindowContentRegionWidth() function. keep inline redirection helper. can use 'GetWindowContentRegionMax().x - GetWindowContentRegionMin().x' instead for generally 'GetContentRegionAvail().x' is more useful.
 - 2021/07/26 (1.84) - commented out redirecting functions/enums names that were marked obsolete in 1.67 and 1.69 (March 2019):
                        - ImGui::GetOverlayDrawList() -> use ImGui::GetForegroundDrawList()
                        - ImFont::GlyphRangesBuilder  -> use ImFontGlyphRangesBuilder
 - 2021/05/19 (1.83) - backends: obsoleted direct access to ImDrawCmd::TextureId in favor of calling ImDrawCmd::GetTexID().
                        - if you are using official backends from the source tree: you have nothing to do.
                        - if you have copied old backend code or using your own: change access to draw_cmd->TextureId to draw_cmd->GetTexID().
 - 2021/03/12 (1.82) - upgraded ImDrawList::AddRect(), AddRectFilled(), PathRect() to use ImDrawFlags instead of ImDrawCornersFlags.
                        - ImDrawCornerFlags_TopLeft  -> use ImDrawFlags_RoundCornersTopLeft
                        - ImDrawCornerFlags_BotRight -> use ImDrawFlags_RoundCornersBottomRight
                        - ImDrawCornerFlags_None     -> use ImDrawFlags_RoundCornersNone etc.
                       flags now sanely defaults to 0 instead of 0x0F, consistent with all other flags in the API.
                       breaking: the default with rounding > 0.0f is now "round all corners" vs old implicit "round no corners":
                        - rounding == 0.0f + flags == 0 --> meant no rounding  --> unchanged (common use)
                        - rounding  > 0.0f + flags != 0 --> meant rounding     --> unchanged (common use)
                        - rounding == 0.0f + flags != 0 --> meant no rounding  --> unchanged (unlikely use)
                        - rounding  > 0.0f + flags == 0 --> meant no rounding  --> BREAKING (unlikely use): will now round all corners --> use ImDrawFlags_RoundCornersNone or rounding == 0.0f.
                       this ONLY matters for hard coded use of 0 + rounding > 0.0f. Use of named ImDrawFlags_RoundCornersNone (new) or ImDrawCornerFlags_None (old) are ok.
                       the old ImDrawCornersFlags used awkward default values of ~0 or 0xF (4 lower bits set) to signify "round all corners" and we sometimes encouraged using them as shortcuts.
                       legacy path still support use of hard coded ~0 or any value from 0x1 or 0xF. They will behave the same with legacy paths enabled (will assert otherwise).
 - 2021/03/11 (1.82) - removed redirecting functions/enums names that were marked obsolete in 1.66 (September 2018):
                        - ImGui::SetScrollHere()              -> use ImGui::SetScrollHereY()
 - 2021/03/11 (1.82) - clarified that ImDrawList::PathArcTo(), ImDrawList::PathArcToFast() won't render with radius < 0.0f. Previously it sorts of accidentally worked but would generally lead to counter-clockwise paths and have an effect on anti-aliasing.
 - 2021/03/10 (1.82) - upgraded ImDrawList::AddPolyline() and PathStroke() "bool closed" parameter to "ImDrawFlags flags". The matching ImDrawFlags_Closed value is guaranteed to always stay == 1 in the future.
 - 2021/02/22 (1.82) - (*undone in 1.84*) win32+mingw: Re-enabled IME functions by default even under MinGW. In July 2016, issue #738 had me incorrectly disable those default functions for MinGW. MinGW users should: either link with -limm32, either set their imconfig file  with '#define IMGUI_DISABLE_WIN32_DEFAULT_IME_FUNCTIONS'.
 - 2021/02/17 (1.82) - renamed rarely used style.CircleSegmentMaxError (old default = 1.60f) to style.CircleTessellationMaxError (new default = 0.30f) as the meaning of the value changed.
 - 2021/02/03 (1.81) - renamed ListBoxHeader(const char* label, ImVec2 size) to BeginListBox(). Kept inline redirection function (will obsolete).
                     - removed ListBoxHeader(const char* label, int items_count, int height_in_items = -1) in favor of specifying size. Kept inline redirection function (will obsolete).
                     - renamed ListBoxFooter() to EndListBox(). Kept inline redirection function (will obsolete).
 - 2021/01/26 (1.81) - removed ImGuiFreeType::BuildFontAtlas(). Kept inline redirection function. Prefer using '#define IMGUI_ENABLE_FREETYPE', but there's a runtime selection path available too. The shared extra flags parameters (very rarely used) are now stored in ImFontAtlas::FontBuilderFlags.
                     - renamed ImFontConfig::RasterizerFlags (used by FreeType) to ImFontConfig::FontBuilderFlags.
                     - renamed ImGuiFreeType::XXX flags to ImGuiFreeTypeBuilderFlags_XXX for consistency with other API.
 - 2020/10/12 (1.80) - removed redirecting functions/enums that were marked obsolete in 1.63 (August 2018):
                        - ImGui::IsItemDeactivatedAfterChange() -> use ImGui::IsItemDeactivatedAfterEdit().
                        - ImGuiCol_ModalWindowDarkening       -> use ImGuiCol_ModalWindowDimBg
                        - ImGuiInputTextCallback              -> use ImGuiTextEditCallback
                        - ImGuiInputTextCallbackData          -> use ImGuiTextEditCallbackData
 - 2020/12/21 (1.80) - renamed ImDrawList::AddBezierCurve() to AddBezierCubic(), and PathBezierCurveTo() to PathBezierCubicCurveTo(). Kept inline redirection function (will obsolete).
 - 2020/12/04 (1.80) - added imgui_tables.cpp file! Manually constructed project files will need the new file added!
 - 2020/11/18 (1.80) - renamed undocumented/internals ImGuiColumnsFlags_* to ImGuiOldColumnFlags_* in prevision of incoming Tables API.
 - 2020/11/03 (1.80) - renamed io.ConfigWindowsMemoryCompactTimer to io.ConfigMemoryCompactTimer as the feature will apply to other data structures
 - 2020/10/14 (1.80) - backends: moved all backends files (imgui_impl_XXXX.cpp, imgui_impl_XXXX.h) from examples/ to backends/.
 - 2020/10/12 (1.80) - removed redirecting functions/enums that were marked obsolete in 1.60 (April 2018):
                        - io.RenderDrawListsFn pointer        -> use ImGui::GetDrawData() value and call the render function of your backend
                        - ImGui::IsAnyWindowFocused()         -> use ImGui::IsWindowFocused(ImGuiFocusedFlags_AnyWindow)
                        - ImGui::IsAnyWindowHovered()         -> use ImGui::IsWindowHovered(ImGuiHoveredFlags_AnyWindow)
                        - ImGuiStyleVar_Count_                -> use ImGuiStyleVar_COUNT
                        - ImGuiMouseCursor_Count_             -> use ImGuiMouseCursor_COUNT
                      - removed redirecting functions names that were marked obsolete in 1.61 (May 2018):
                        - InputFloat (... int decimal_precision ...) -> use InputFloat (... const char* format ...) with format = "%.Xf" where X is your value for decimal_precision.
                        - same for InputFloat2()/InputFloat3()/InputFloat4() variants taking a `int decimal_precision` parameter.
 - 2020/10/05 (1.79) - removed ImGuiListClipper: Renamed constructor parameters which created an ambiguous alternative to using the ImGuiListClipper::Begin() function, with misleading edge cases (note: imgui_memory_editor <0.40 from imgui_club/ used this old clipper API. Update your copy if needed).
 - 2020/09/25 (1.79) - renamed ImGuiSliderFlags_ClampOnInput to ImGuiSliderFlags_AlwaysClamp. Kept redirection enum (will obsolete sooner because previous name was added recently).
 - 2020/09/25 (1.79) - renamed style.TabMinWidthForUnselectedCloseButton to style.TabMinWidthForCloseButton.
 - 2020/09/21 (1.79) - renamed OpenPopupContextItem() back to OpenPopupOnItemClick(), reverting the change from 1.77. For varieties of reason this is more self-explanatory.
 - 2020/09/21 (1.79) - removed return value from OpenPopupOnItemClick() - returned true on mouse release on an item - because it is inconsistent with other popup APIs and makes others misleading. It's also and unnecessary: you can use IsWindowAppearing() after BeginPopup() for a similar result.
 - 2020/09/17 (1.79) - removed ImFont::DisplayOffset in favor of ImFontConfig::GlyphOffset. DisplayOffset was applied after scaling and not very meaningful/useful outside of being needed by the default ProggyClean font. If you scaled this value after calling AddFontDefault(), this is now done automatically. It was also getting in the way of better font scaling, so let's get rid of it now!
 - 2020/08/17 (1.78) - obsoleted use of the trailing 'float power=1.0f' parameter for DragFloat(), DragFloat2(), DragFloat3(), DragFloat4(), DragFloatRange2(), DragScalar(), DragScalarN(), SliderFloat(), SliderFloat2(), SliderFloat3(), SliderFloat4(), SliderScalar(), SliderScalarN(), VSliderFloat() and VSliderScalar().
                       replaced the 'float power=1.0f' argument with integer-based flags defaulting to 0 (as with all our flags).
                       worked out a backward-compatibility scheme so hopefully most C++ codebase should not be affected. in short, when calling those functions:
                       - if you omitted the 'power' parameter (likely!), you are not affected.
                       - if you set the 'power' parameter to 1.0f (same as previous default value): 1/ your compiler may warn on float>int conversion, 2/ everything else will work. 3/ you can replace the 1.0f value with 0 to fix the warning, and be technically correct.
                       - if you set the 'power' parameter to >1.0f (to enable non-linear editing): 1/ your compiler may warn on float>int conversion, 2/ code will assert at runtime, 3/ in case asserts are disabled, the code will not crash and enable the _Logarithmic flag. 4/ you can replace the >1.0f value with ImGuiSliderFlags_Logarithmic to fix the warning/assert and get a _similar_ effect as previous uses of power >1.0f.
                       see https://github.com/ocornut/imgui/issues/3361 for all details.
                       kept inline redirection functions (will obsolete) apart for: DragFloatRange2(), VSliderFloat(), VSliderScalar(). For those three the 'float power=1.0f' version was removed directly as they were most unlikely ever used.
                       for shared code, you can version check at compile-time with `#if IMGUI_VERSION_NUM >= 17704`.
                     - obsoleted use of v_min > v_max in DragInt, DragFloat, DragScalar to lock edits (introduced in 1.73, was not demoed nor documented very), will be replaced by a more generic ReadOnly feature. You may use the ImGuiSliderFlags_ReadOnly internal flag in the meantime.
 - 2020/06/23 (1.77) - removed BeginPopupContextWindow(const char*, int mouse_button, bool also_over_items) in favor of BeginPopupContextWindow(const char*, ImGuiPopupFlags flags) with ImGuiPopupFlags_NoOverItems.
 - 2020/06/15 (1.77) - renamed OpenPopupOnItemClick() to OpenPopupContextItem(). Kept inline redirection function (will obsolete). [NOTE: THIS WAS REVERTED IN 1.79]
 - 2020/06/15 (1.77) - removed CalcItemRectClosestPoint() entry point which was made obsolete and asserting in December 2017.
 - 2020/04/23 (1.77) - removed unnecessary ID (first arg) of ImFontAtlas::AddCustomRectRegular().
 - 2020/01/22 (1.75) - ImDrawList::AddCircle()/AddCircleFilled() functions don't accept negative radius any more.
 - 2019/12/17 (1.75) - [undid this change in 1.76] made Columns() limited to 64 columns by asserting above that limit. While the current code technically supports it, future code may not so we're putting the restriction ahead.
 - 2019/12/13 (1.75) - [imgui_internal.h] changed ImRect() default constructor initializes all fields to 0.0f instead of (FLT_MAX,FLT_MAX,-FLT_MAX,-FLT_MAX). If you used ImRect::Add() to create bounding boxes by adding multiple points into it, you may need to fix your initial value.
 - 2019/12/08 (1.75) - removed redirecting functions/enums that were marked obsolete in 1.53 (December 2017):
                       - ShowTestWindow()                    -> use ShowDemoWindow()
                       - IsRootWindowFocused()               -> use IsWindowFocused(ImGuiFocusedFlags_RootWindow)
                       - IsRootWindowOrAnyChildFocused()     -> use IsWindowFocused(ImGuiFocusedFlags_RootAndChildWindows)
                       - SetNextWindowContentWidth(w)        -> use SetNextWindowContentSize(ImVec2(w, 0.0f)
                       - GetItemsLineHeightWithSpacing()     -> use GetFrameHeightWithSpacing()
                       - ImGuiCol_ChildWindowBg              -> use ImGuiCol_ChildBg
                       - ImGuiStyleVar_ChildWindowRounding   -> use ImGuiStyleVar_ChildRounding
                       - ImGuiTreeNodeFlags_AllowOverlapMode -> use ImGuiTreeNodeFlags_AllowItemOverlap
                       - IMGUI_DISABLE_TEST_WINDOWS          -> use IMGUI_DISABLE_DEMO_WINDOWS
 - 2019/12/08 (1.75) - obsoleted calling ImDrawList::PrimReserve() with a negative count (which was vaguely documented and rarely if ever used). Instead, we added an explicit PrimUnreserve() API.
 - 2019/12/06 (1.75) - removed implicit default parameter to IsMouseDragging(int button = 0) to be consistent with other mouse functions (none of the other functions have it).
 - 2019/11/21 (1.74) - ImFontAtlas::AddCustomRectRegular() now requires an ID larger than 0x110000 (instead of 0x10000) to conform with supporting Unicode planes 1-16 in a future update. ID below 0x110000 will now assert.
 - 2019/11/19 (1.74) - renamed IMGUI_DISABLE_FORMAT_STRING_FUNCTIONS to IMGUI_DISABLE_DEFAULT_FORMAT_FUNCTIONS for consistency.
 - 2019/11/19 (1.74) - renamed IMGUI_DISABLE_MATH_FUNCTIONS to IMGUI_DISABLE_DEFAULT_MATH_FUNCTIONS for consistency.
 - 2019/10/22 (1.74) - removed redirecting functions/enums that were marked obsolete in 1.52 (October 2017):
                       - Begin() [old 5 args version]        -> use Begin() [3 args], use SetNextWindowSize() SetNextWindowBgAlpha() if needed
                       - IsRootWindowOrAnyChildHovered()     -> use IsWindowHovered(ImGuiHoveredFlags_RootAndChildWindows)
                       - AlignFirstTextHeightToWidgets()     -> use AlignTextToFramePadding()
                       - SetNextWindowPosCenter()            -> use SetNextWindowPos() with a pivot of (0.5f, 0.5f)
                       - ImFont::Glyph                       -> use ImFontGlyph
 - 2019/10/14 (1.74) - inputs: Fixed a miscalculation in the keyboard/mouse "typematic" repeat delay/rate calculation, used by keys and e.g. repeating mouse buttons as well as the GetKeyPressedAmount() function.
                       if you were using a non-default value for io.KeyRepeatRate (previous default was 0.250), you can add +io.KeyRepeatDelay to it to compensate for the fix.
                       The function was triggering on: 0.0 and (delay+rate*N) where (N>=1). Fixed formula responds to (N>=0). Effectively it made io.KeyRepeatRate behave like it was set to (io.KeyRepeatRate + io.KeyRepeatDelay).
                       If you never altered io.KeyRepeatRate nor used GetKeyPressedAmount() this won't affect you.
 - 2019/07/15 (1.72) - removed TreeAdvanceToLabelPos() which is rarely used and only does SetCursorPosX(GetCursorPosX() + GetTreeNodeToLabelSpacing()). Kept redirection function (will obsolete).
 - 2019/07/12 (1.72) - renamed ImFontAtlas::CustomRect to ImFontAtlasCustomRect. Kept redirection typedef (will obsolete).
 - 2019/06/14 (1.72) - removed redirecting functions/enums names that were marked obsolete in 1.51 (June 2017): ImGuiCol_Column*, ImGuiSetCond_*, IsItemHoveredRect(), IsPosHoveringAnyWindow(), IsMouseHoveringAnyWindow(), IsMouseHoveringWindow(), IMGUI_ONCE_UPON_A_FRAME. Grep this log for details and new names, or see how they were implemented until 1.71.
 - 2019/06/07 (1.71) - rendering of child window outer decorations (bg color, border, scrollbars) is now performed as part of the parent window. If you have
                       overlapping child windows in a same parent, and relied on their relative z-order to be mapped to their submission order, this will affect your rendering.
                       This optimization is disabled if the parent window has no visual output, because it appears to be the most common situation leading to the creation of overlapping child windows.
                       Please reach out if you are affected.
 - 2019/05/13 (1.71) - renamed SetNextTreeNodeOpen() to SetNextItemOpen(). Kept inline redirection function (will obsolete).
 - 2019/05/11 (1.71) - changed io.AddInputCharacter(unsigned short c) signature to io.AddInputCharacter(unsigned int c).
 - 2019/04/29 (1.70) - improved ImDrawList thick strokes (>1.0f) preserving correct thickness up to 90 degrees angles (e.g. rectangles). If you have custom rendering using thick lines, they will appear thicker now.
 - 2019/04/29 (1.70) - removed GetContentRegionAvailWidth(), use GetContentRegionAvail().x instead. Kept inline redirection function (will obsolete).
 - 2019/03/04 (1.69) - renamed GetOverlayDrawList() to GetForegroundDrawList(). Kept redirection function (will obsolete).
 - 2019/02/26 (1.69) - renamed ImGuiColorEditFlags_RGB/ImGuiColorEditFlags_HSV/ImGuiColorEditFlags_HEX to ImGuiColorEditFlags_DisplayRGB/ImGuiColorEditFlags_DisplayHSV/ImGuiColorEditFlags_DisplayHex. Kept redirection enums (will obsolete).
 - 2019/02/14 (1.68) - made it illegal/assert when io.DisplayTime == 0.0f (with an exception for the first frame). If for some reason your time step calculation gives you a zero value, replace it with an arbitrarily small value!
 - 2019/02/01 (1.68) - removed io.DisplayVisibleMin/DisplayVisibleMax (which were marked obsolete and removed from viewport/docking branch already).
 - 2019/01/06 (1.67) - renamed io.InputCharacters[], marked internal as was always intended. Please don't access directly, and use AddInputCharacter() instead!
 - 2019/01/06 (1.67) - renamed ImFontAtlas::GlyphRangesBuilder to ImFontGlyphRangesBuilder. Kept redirection typedef (will obsolete).
 - 2018/12/20 (1.67) - made it illegal to call Begin("") with an empty string. This somehow half-worked before but had various undesirable side-effects.
 - 2018/12/10 (1.67) - renamed io.ConfigResizeWindowsFromEdges to io.ConfigWindowsResizeFromEdges as we are doing a large pass on configuration flags.
 - 2018/10/12 (1.66) - renamed misc/stl/imgui_stl.* to misc/cpp/imgui_stdlib.* in prevision for other C++ helper files.
 - 2018/09/28 (1.66) - renamed SetScrollHere() to SetScrollHereY(). Kept redirection function (will obsolete).
 - 2018/09/06 (1.65) - renamed stb_truetype.h to imstb_truetype.h, stb_textedit.h to imstb_textedit.h, and stb_rect_pack.h to imstb_rectpack.h.
                       If you were conveniently using the imgui copy of those STB headers in your project you will have to update your include paths.
 - 2018/09/05 (1.65) - renamed io.OptCursorBlink/io.ConfigCursorBlink to io.ConfigInputTextCursorBlink. (#1427)
 - 2018/08/31 (1.64) - added imgui_widgets.cpp file, extracted and moved widgets code out of imgui.cpp into imgui_widgets.cpp. Re-ordered some of the code remaining in imgui.cpp.
                       NONE OF THE FUNCTIONS HAVE CHANGED. THE CODE IS SEMANTICALLY 100% IDENTICAL, BUT _EVERY_ FUNCTION HAS BEEN MOVED.
                       Because of this, any local modifications to imgui.cpp will likely conflict when you update. Read docs/CHANGELOG.txt for suggestions.
 - 2018/08/22 (1.63) - renamed IsItemDeactivatedAfterChange() to IsItemDeactivatedAfterEdit() for consistency with new IsItemEdited() API. Kept redirection function (will obsolete soonish as IsItemDeactivatedAfterChange() is very recent).
 - 2018/08/21 (1.63) - renamed ImGuiTextEditCallback to ImGuiInputTextCallback, ImGuiTextEditCallbackData to ImGuiInputTextCallbackData for consistency. Kept redirection types (will obsolete).
 - 2018/08/21 (1.63) - removed ImGuiInputTextCallbackData::ReadOnly since it is a duplication of (ImGuiInputTextCallbackData::Flags & ImGuiInputTextFlags_ReadOnly).
 - 2018/08/01 (1.63) - removed per-window ImGuiWindowFlags_ResizeFromAnySide beta flag in favor of a global io.ConfigResizeWindowsFromEdges [update 1.67 renamed to ConfigWindowsResizeFromEdges] to enable the feature.
 - 2018/08/01 (1.63) - renamed io.OptCursorBlink to io.ConfigCursorBlink [-> io.ConfigInputTextCursorBlink in 1.65], io.OptMacOSXBehaviors to ConfigMacOSXBehaviors for consistency.
 - 2018/07/22 (1.63) - changed ImGui::GetTime() return value from float to double to avoid accumulating floating point imprecisions over time.
 - 2018/07/08 (1.63) - style: renamed ImGuiCol_ModalWindowDarkening to ImGuiCol_ModalWindowDimBg for consistency with other features. Kept redirection enum (will obsolete).
 - 2018/06/08 (1.62) - examples: the imgui_impl_XXX files have been split to separate platform (Win32, GLFW, SDL2, etc.) from renderer (DX11, OpenGL, Vulkan,  etc.).
                       old backends will still work as is, however prefer using the separated backends as they will be updated to support multi-viewports.
                       when adopting new backends follow the main.cpp code of your preferred examples/ folder to know which functions to call.
                       in particular, note that old backends called ImGui::NewFrame() at the end of their ImGui_ImplXXXX_NewFrame() function.
 - 2018/06/06 (1.62) - renamed GetGlyphRangesChinese() to GetGlyphRangesChineseFull() to distinguish other variants and discourage using the full set.
 - 2018/06/06 (1.62) - TreeNodeEx()/TreeNodeBehavior(): the ImGuiTreeNodeFlags_CollapsingHeader helper now include the ImGuiTreeNodeFlags_NoTreePushOnOpen flag. See Changelog for details.
 - 2018/05/03 (1.61) - DragInt(): the default compile-time format string has been changed from "%.0f" to "%d", as we are not using integers internally any more.
                       If you used DragInt() with custom format strings, make sure you change them to use %d or an integer-compatible format.
                       To honor backward-compatibility, the DragInt() code will currently parse and modify format strings to replace %*f with %d, giving time to users to upgrade their code.
                       If you have IMGUI_DISABLE_OBSOLETE_FUNCTIONS enabled, the code will instead assert! You may run a reg-exp search on your codebase for e.g. "DragInt.*%f" to help you find them.
 - 2018/04/28 (1.61) - obsoleted InputFloat() functions taking an optional "int decimal_precision" in favor of an equivalent and more flexible "const char* format",
                       consistent with other functions. Kept redirection functions (will obsolete).
 - 2018/04/09 (1.61) - IM_DELETE() helper function added in 1.60 doesn't clear the input _pointer_ reference, more consistent with expectation and allows passing r-value.
 - 2018/03/20 (1.60) - renamed io.WantMoveMouse to io.WantSetMousePos for consistency and ease of understanding (was added in 1.52, _not_ used by core and only honored by some backend ahead of merging the Nav branch).
 - 2018/03/12 (1.60) - removed ImGuiCol_CloseButton, ImGuiCol_CloseButtonActive, ImGuiCol_CloseButtonHovered as the closing cross uses regular button colors now.
 - 2018/03/08 (1.60) - changed ImFont::DisplayOffset.y to default to 0 instead of +1. Fixed rounding of Ascent/Descent to match TrueType renderer. If you were adding or subtracting to ImFont::DisplayOffset check if your fonts are correctly aligned vertically.
 - 2018/03/03 (1.60) - renamed ImGuiStyleVar_Count_ to ImGuiStyleVar_COUNT and ImGuiMouseCursor_Count_ to ImGuiMouseCursor_COUNT for consistency with other public enums.
 - 2018/02/18 (1.60) - BeginDragDropSource(): temporarily removed the optional mouse_button=0 parameter because it is not really usable in many situations at the moment.
 - 2018/02/16 (1.60) - obsoleted the io.RenderDrawListsFn callback, you can call your graphics engine render function after ImGui::Render(). Use ImGui::GetDrawData() to retrieve the ImDrawData* to display.
 - 2018/02/07 (1.60) - reorganized context handling to be more explicit,
                       - YOU NOW NEED TO CALL ImGui::CreateContext() AT THE BEGINNING OF YOUR APP, AND CALL ImGui::DestroyContext() AT THE END.
                       - removed Shutdown() function, as DestroyContext() serve this purpose.
                       - you may pass a ImFontAtlas* pointer to CreateContext() to share a font atlas between contexts. Otherwise CreateContext() will create its own font atlas instance.
                       - removed allocator parameters from CreateContext(), they are now setup with SetAllocatorFunctions(), and shared by all contexts.
                       - removed the default global context and font atlas instance, which were confusing for users of DLL reloading and users of multiple contexts.
 - 2018/01/31 (1.60) - moved sample TTF files from extra_fonts/ to misc/fonts/. If you loaded files directly from the imgui repo you may need to update your paths.
 - 2018/01/11 (1.60) - obsoleted IsAnyWindowHovered() in favor of IsWindowHovered(ImGuiHoveredFlags_AnyWindow). Kept redirection function (will obsolete).
 - 2018/01/11 (1.60) - obsoleted IsAnyWindowFocused() in favor of IsWindowFocused(ImGuiFocusedFlags_AnyWindow). Kept redirection function (will obsolete).
 - 2018/01/03 (1.60) - renamed ImGuiSizeConstraintCallback to ImGuiSizeCallback, ImGuiSizeConstraintCallbackData to ImGuiSizeCallbackData.
 - 2017/12/29 (1.60) - removed CalcItemRectClosestPoint() which was weird and not really used by anyone except demo code. If you need it it's easy to replicate on your side.
 - 2017/12/24 (1.53) - renamed the emblematic ShowTestWindow() function to ShowDemoWindow(). Kept redirection function (will obsolete).
 - 2017/12/21 (1.53) - ImDrawList: renamed style.AntiAliasedShapes to style.AntiAliasedFill for consistency and as a way to explicitly break code that manipulate those flag at runtime. You can now manipulate ImDrawList::Flags
 - 2017/12/21 (1.53) - ImDrawList: removed 'bool anti_aliased = true' final parameter of ImDrawList::AddPolyline() and ImDrawList::AddConvexPolyFilled(). Prefer manipulating ImDrawList::Flags if you need to toggle them during the frame.
 - 2017/12/14 (1.53) - using the ImGuiWindowFlags_NoScrollWithMouse flag on a child window forwards the mouse wheel event to the parent window, unless either ImGuiWindowFlags_NoInputs or ImGuiWindowFlags_NoScrollbar are also set.
 - 2017/12/13 (1.53) - renamed GetItemsLineHeightWithSpacing() to GetFrameHeightWithSpacing(). Kept redirection function (will obsolete).
 - 2017/12/13 (1.53) - obsoleted IsRootWindowFocused() in favor of using IsWindowFocused(ImGuiFocusedFlags_RootWindow). Kept redirection function (will obsolete).
                     - obsoleted IsRootWindowOrAnyChildFocused() in favor of using IsWindowFocused(ImGuiFocusedFlags_RootAndChildWindows). Kept redirection function (will obsolete).
 - 2017/12/12 (1.53) - renamed ImGuiTreeNodeFlags_AllowOverlapMode to ImGuiTreeNodeFlags_AllowItemOverlap. Kept redirection enum (will obsolete).
 - 2017/12/10 (1.53) - removed SetNextWindowContentWidth(), prefer using SetNextWindowContentSize(). Kept redirection function (will obsolete).
 - 2017/11/27 (1.53) - renamed ImGuiTextBuffer::append() helper to appendf(), appendv() to appendfv(). If you copied the 'Log' demo in your code, it uses appendv() so that needs to be renamed.
 - 2017/11/18 (1.53) - Style, Begin: removed ImGuiWindowFlags_ShowBorders window flag. Borders are now fully set up in the ImGuiStyle structure (see e.g. style.FrameBorderSize, style.WindowBorderSize). Use ImGui::ShowStyleEditor() to look them up.
                       Please note that the style system will keep evolving (hopefully stabilizing in Q1 2018), and so custom styles will probably subtly break over time. It is recommended you use the StyleColorsClassic(), StyleColorsDark(), StyleColorsLight() functions.
 - 2017/11/18 (1.53) - Style: removed ImGuiCol_ComboBg in favor of combo boxes using ImGuiCol_PopupBg for consistency.
 - 2017/11/18 (1.53) - Style: renamed ImGuiCol_ChildWindowBg to ImGuiCol_ChildBg.
 - 2017/11/18 (1.53) - Style: renamed style.ChildWindowRounding to style.ChildRounding, ImGuiStyleVar_ChildWindowRounding to ImGuiStyleVar_ChildRounding.
 - 2017/11/02 (1.53) - obsoleted IsRootWindowOrAnyChildHovered() in favor of using IsWindowHovered(ImGuiHoveredFlags_RootAndChildWindows);
 - 2017/10/24 (1.52) - renamed IMGUI_DISABLE_WIN32_DEFAULT_CLIPBOARD_FUNCS/IMGUI_DISABLE_WIN32_DEFAULT_IME_FUNCS to IMGUI_DISABLE_WIN32_DEFAULT_CLIPBOARD_FUNCTIONS/IMGUI_DISABLE_WIN32_DEFAULT_IME_FUNCTIONS for consistency.
 - 2017/10/20 (1.52) - changed IsWindowHovered() default parameters behavior to return false if an item is active in another window (e.g. click-dragging item from another window to this window). You can use the newly introduced IsWindowHovered() flags to requests this specific behavior if you need it.
 - 2017/10/20 (1.52) - marked IsItemHoveredRect()/IsMouseHoveringWindow() as obsolete, in favor of using the newly introduced flags for IsItemHovered() and IsWindowHovered(). See https://github.com/ocornut/imgui/issues/1382 for details.
                       removed the IsItemRectHovered()/IsWindowRectHovered() names introduced in 1.51 since they were merely more consistent names for the two functions we are now obsoleting.
                         IsItemHoveredRect()        --> IsItemHovered(ImGuiHoveredFlags_RectOnly)
                         IsMouseHoveringAnyWindow() --> IsWindowHovered(ImGuiHoveredFlags_AnyWindow)
                         IsMouseHoveringWindow()    --> IsWindowHovered(ImGuiHoveredFlags_AllowWhenBlockedByPopup | ImGuiHoveredFlags_AllowWhenBlockedByActiveItem) [weird, old behavior]
 - 2017/10/17 (1.52) - marked the old 5-parameters version of Begin() as obsolete (still available). Use SetNextWindowSize()+Begin() instead!
 - 2017/10/11 (1.52) - renamed AlignFirstTextHeightToWidgets() to AlignTextToFramePadding(). Kept inline redirection function (will obsolete).
 - 2017/09/26 (1.52) - renamed ImFont::Glyph to ImFontGlyph. Kept redirection typedef (will obsolete).
 - 2017/09/25 (1.52) - removed SetNextWindowPosCenter() because SetNextWindowPos() now has the optional pivot information to do the same and more. Kept redirection function (will obsolete).
 - 2017/08/25 (1.52) - io.MousePos needs to be set to ImVec2(-FLT_MAX,-FLT_MAX) when mouse is unavailable/missing. Previously ImVec2(-1,-1) was enough but we now accept negative mouse coordinates. In your backend if you need to support unavailable mouse, make sure to replace "io.MousePos = ImVec2(-1,-1)" with "io.MousePos = ImVec2(-FLT_MAX,-FLT_MAX)".
 - 2017/08/22 (1.51) - renamed IsItemHoveredRect() to IsItemRectHovered(). Kept inline redirection function (will obsolete). -> (1.52) use IsItemHovered(ImGuiHoveredFlags_RectOnly)!
                     - renamed IsMouseHoveringAnyWindow() to IsAnyWindowHovered() for consistency. Kept inline redirection function (will obsolete).
                     - renamed IsMouseHoveringWindow() to IsWindowRectHovered() for consistency. Kept inline redirection function (will obsolete).
 - 2017/08/20 (1.51) - renamed GetStyleColName() to GetStyleColorName() for consistency.
 - 2017/08/20 (1.51) - added PushStyleColor(ImGuiCol idx, ImU32 col) overload, which _might_ cause an "ambiguous call" compilation error if you are using ImColor() with implicit cast. Cast to ImU32 or ImVec4 explicily to fix.
 - 2017/08/15 (1.51) - marked the weird IMGUI_ONCE_UPON_A_FRAME helper macro as obsolete. prefer using the more explicit ImGuiOnceUponAFrame type.
 - 2017/08/15 (1.51) - changed parameter order for BeginPopupContextWindow() from (const char*,int buttons,bool also_over_items) to (const char*,int buttons,bool also_over_items). Note that most calls relied on default parameters completely.
 - 2017/08/13 (1.51) - renamed ImGuiCol_Column to ImGuiCol_Separator, ImGuiCol_ColumnHovered to ImGuiCol_SeparatorHovered, ImGuiCol_ColumnActive to ImGuiCol_SeparatorActive. Kept redirection enums (will obsolete).
 - 2017/08/11 (1.51) - renamed ImGuiSetCond_Always to ImGuiCond_Always, ImGuiSetCond_Once to ImGuiCond_Once, ImGuiSetCond_FirstUseEver to ImGuiCond_FirstUseEver, ImGuiSetCond_Appearing to ImGuiCond_Appearing. Kept redirection enums (will obsolete).
 - 2017/08/09 (1.51) - removed ValueColor() helpers, they are equivalent to calling Text(label) + SameLine() + ColorButton().
 - 2017/08/08 (1.51) - removed ColorEditMode() and ImGuiColorEditMode in favor of ImGuiColorEditFlags and parameters to the various Color*() functions. The SetColorEditOptions() allows to initialize default but the user can still change them with right-click context menu.
                     - changed prototype of 'ColorEdit4(const char* label, float col[4], bool show_alpha = true)' to 'ColorEdit4(const char* label, float col[4], ImGuiColorEditFlags flags = 0)', where passing flags = 0x01 is a safe no-op (hello dodgy backward compatibility!). - check and run the demo window, under "Color/Picker Widgets", to understand the various new options.
                     - changed prototype of rarely used 'ColorButton(ImVec4 col, bool small_height = false, bool outline_border = true)' to 'ColorButton(const char* desc_id, ImVec4 col, ImGuiColorEditFlags flags = 0, ImVec2 size = ImVec2(0, 0))'
 - 2017/07/20 (1.51) - removed IsPosHoveringAnyWindow(ImVec2), which was partly broken and misleading. ASSERT + redirect user to io.WantCaptureMouse
 - 2017/05/26 (1.50) - removed ImFontConfig::MergeGlyphCenterV in favor of a more multipurpose ImFontConfig::GlyphOffset.
 - 2017/05/01 (1.50) - renamed ImDrawList::PathFill() (rarely used directly) to ImDrawList::PathFillConvex() for clarity.
 - 2016/11/06 (1.50) - BeginChild(const char*) now applies the stack id to the provided label, consistently with other functions as it should always have been. It shouldn't affect you unless (extremely unlikely) you were appending multiple times to a same child from different locations of the stack id. If that's the case, generate an id with GetID() and use it instead of passing string to BeginChild().
 - 2016/10/15 (1.50) - avoid 'void* user_data' parameter to io.SetClipboardTextFn/io.GetClipboardTextFn pointers. We pass io.ClipboardUserData to it.
 - 2016/09/25 (1.50) - style.WindowTitleAlign is now a ImVec2 (ImGuiAlign enum was removed). set to (0.5f,0.5f) for horizontal+vertical centering, (0.0f,0.0f) for upper-left, etc.
 - 2016/07/30 (1.50) - SameLine(x) with x>0.0f is now relative to left of column/group if any, and not always to left of window. This was sort of always the intent and hopefully, breakage should be minimal.
 - 2016/05/12 (1.49) - title bar (using ImGuiCol_TitleBg/ImGuiCol_TitleBgActive colors) isn't rendered over a window background (ImGuiCol_WindowBg color) anymore.
                       If your TitleBg/TitleBgActive alpha was 1.0f or you are using the default theme it will not affect you, otherwise if <1.0f you need to tweak your custom theme to readjust for the fact that we don't draw a WindowBg background behind the title bar.
                       This helper function will convert an old TitleBg/TitleBgActive color into a new one with the same visual output, given the OLD color and the OLD WindowBg color:
                       ImVec4 ConvertTitleBgCol(const ImVec4& win_bg_col, const ImVec4& title_bg_col) { float new_a = 1.0f - ((1.0f - win_bg_col.w) * (1.0f - title_bg_col.w)), k = title_bg_col.w / new_a; return ImVec4((win_bg_col.x * win_bg_col.w + title_bg_col.x) * k, (win_bg_col.y * win_bg_col.w + title_bg_col.y) * k, (win_bg_col.z * win_bg_col.w + title_bg_col.z) * k, new_a); }
                       If this is confusing, pick the RGB value from title bar from an old screenshot and apply this as TitleBg/TitleBgActive. Or you may just create TitleBgActive from a tweaked TitleBg color.
 - 2016/05/07 (1.49) - removed confusing set of GetInternalState(), GetInternalStateSize(), SetInternalState() functions. Now using CreateContext(), DestroyContext(), GetCurrentContext(), SetCurrentContext().
 - 2016/05/02 (1.49) - renamed SetNextTreeNodeOpened() to SetNextTreeNodeOpen(), no redirection.
 - 2016/05/01 (1.49) - obsoleted old signature of CollapsingHeader(const char* label, const char* str_id = NULL, bool display_frame = true, bool default_open = false) as extra parameters were badly designed and rarely used. You can replace the "default_open = true" flag in new API with CollapsingHeader(label, ImGuiTreeNodeFlags_DefaultOpen).
 - 2016/04/26 (1.49) - changed ImDrawList::PushClipRect(ImVec4 rect) to ImDrawList::PushClipRect(Imvec2 min,ImVec2 max,bool intersect_with_current_clip_rect=false). Note that higher-level ImGui::PushClipRect() is preferable because it will clip at logic/widget level, whereas ImDrawList::PushClipRect() only affect your renderer.
 - 2016/04/03 (1.48) - removed style.WindowFillAlphaDefault setting which was redundant. Bake default BG alpha inside style.Colors[ImGuiCol_WindowBg] and all other Bg color values. (ref GitHub issue #337).
 - 2016/04/03 (1.48) - renamed ImGuiCol_TooltipBg to ImGuiCol_PopupBg, used by popups/menus and tooltips. popups/menus were previously using ImGuiCol_WindowBg. (ref github issue #337)
 - 2016/03/21 (1.48) - renamed GetWindowFont() to GetFont(), GetWindowFontSize() to GetFontSize(). Kept inline redirection function (will obsolete).
 - 2016/03/02 (1.48) - InputText() completion/history/always callbacks: if you modify the text buffer manually (without using DeleteChars()/InsertChars() helper) you need to maintain the BufTextLen field. added an assert.
 - 2016/01/23 (1.48) - fixed not honoring exact width passed to PushItemWidth(), previously it would add extra FramePadding.x*2 over that width. if you had manual pixel-perfect alignment in place it might affect you.
 - 2015/12/27 (1.48) - fixed ImDrawList::AddRect() which used to render a rectangle 1 px too large on each axis.
 - 2015/12/04 (1.47) - renamed Color() helpers to ValueColor() - dangerously named, rarely used and probably to be made obsolete.
 - 2015/08/29 (1.45) - with the addition of horizontal scrollbar we made various fixes to inconsistencies with dealing with cursor position.
                       GetCursorPos()/SetCursorPos() functions now include the scrolled amount. It shouldn't affect the majority of users, but take note that SetCursorPosX(100.0f) puts you at +100 from the starting x position which may include scrolling, not at +100 from the window left side.
                       GetContentRegionMax()/GetWindowContentRegionMin()/GetWindowContentRegionMax() functions allow include the scrolled amount. Typically those were used in cases where no scrolling would happen so it may not be a problem, but watch out!
 - 2015/08/29 (1.45) - renamed style.ScrollbarWidth to style.ScrollbarSize
 - 2015/08/05 (1.44) - split imgui.cpp into extra files: imgui_demo.cpp imgui_draw.cpp imgui_internal.h that you need to add to your project.
 - 2015/07/18 (1.44) - fixed angles in ImDrawList::PathArcTo(), PathArcToFast() (introduced in 1.43) being off by an extra PI for no justifiable reason
 - 2015/07/14 (1.43) - add new ImFontAtlas::AddFont() API. For the old AddFont***, moved the 'font_no' parameter of ImFontAtlas::AddFont** functions to the ImFontConfig structure.
                       you need to render your textured triangles with bilinear filtering to benefit from sub-pixel positioning of text.
 - 2015/07/08 (1.43) - switched rendering data to use indexed rendering. this is saving a fair amount of CPU/GPU and enables us to get anti-aliasing for a marginal cost.
                       this necessary change will break your rendering function! the fix should be very easy. sorry for that :(
                     - if you are using a vanilla copy of one of the imgui_impl_XXX.cpp provided in the example, you just need to update your copy and you can ignore the rest.
                     - the signature of the io.RenderDrawListsFn handler has changed!
                       old: ImGui_XXXX_RenderDrawLists(ImDrawList** const cmd_lists, int cmd_lists_count)
                       new: ImGui_XXXX_RenderDrawLists(ImDrawData* draw_data).
                         parameters: 'cmd_lists' becomes 'draw_data->CmdLists', 'cmd_lists_count' becomes 'draw_data->CmdListsCount'
                         ImDrawList: 'commands' becomes 'CmdBuffer', 'vtx_buffer' becomes 'VtxBuffer', 'IdxBuffer' is new.
                         ImDrawCmd:  'vtx_count' becomes 'ElemCount', 'clip_rect' becomes 'ClipRect', 'user_callback' becomes 'UserCallback', 'texture_id' becomes 'TextureId'.
                     - each ImDrawList now contains both a vertex buffer and an index buffer. For each command, render ElemCount/3 triangles using indices from the index buffer.
                     - if you REALLY cannot render indexed primitives, you can call the draw_data->DeIndexAllBuffers() method to de-index the buffers. This is slow and a waste of CPU/GPU. Prefer using indexed rendering!
                     - refer to code in the examples/ folder or ask on the GitHub if you are unsure of how to upgrade. please upgrade!
 - 2015/07/10 (1.43) - changed SameLine() parameters from int to float.
 - 2015/07/02 (1.42) - renamed SetScrollPosHere() to SetScrollFromCursorPos(). Kept inline redirection function (will obsolete).
 - 2015/07/02 (1.42) - renamed GetScrollPosY() to GetScrollY(). Necessary to reduce confusion along with other scrolling functions, because positions (e.g. cursor position) are not equivalent to scrolling amount.
 - 2015/06/14 (1.41) - changed ImageButton() default bg_col parameter from (0,0,0,1) (black) to (0,0,0,0) (transparent) - makes a difference when texture have transparence
 - 2015/06/14 (1.41) - changed Selectable() API from (label, selected, size) to (label, selected, flags, size). Size override should have been rarely used. Sorry!
 - 2015/05/31 (1.40) - renamed GetWindowCollapsed() to IsWindowCollapsed() for consistency. Kept inline redirection function (will obsolete).
 - 2015/05/31 (1.40) - renamed IsRectClipped() to IsRectVisible() for consistency. Note that return value is opposite! Kept inline redirection function (will obsolete).
 - 2015/05/27 (1.40) - removed the third 'repeat_if_held' parameter from Button() - sorry! it was rarely used and inconsistent. Use PushButtonRepeat(true) / PopButtonRepeat() to enable repeat on desired buttons.
 - 2015/05/11 (1.40) - changed BeginPopup() API, takes a string identifier instead of a bool. ImGui needs to manage the open/closed state of popups. Call OpenPopup() to actually set the "open" state of a popup. BeginPopup() returns true if the popup is opened.
 - 2015/05/03 (1.40) - removed style.AutoFitPadding, using style.WindowPadding makes more sense (the default values were already the same).
 - 2015/04/13 (1.38) - renamed IsClipped() to IsRectClipped(). Kept inline redirection function until 1.50.
 - 2015/04/09 (1.38) - renamed ImDrawList::AddArc() to ImDrawList::AddArcFast() for compatibility with future API
 - 2015/04/03 (1.38) - removed ImGuiCol_CheckHovered, ImGuiCol_CheckActive, replaced with the more general ImGuiCol_FrameBgHovered, ImGuiCol_FrameBgActive.
 - 2014/04/03 (1.38) - removed support for passing -FLT_MAX..+FLT_MAX as the range for a SliderFloat(). Use DragFloat() or Inputfloat() instead.
 - 2015/03/17 (1.36) - renamed GetItemBoxMin()/GetItemBoxMax()/IsMouseHoveringBox() to GetItemRectMin()/GetItemRectMax()/IsMouseHoveringRect(). Kept inline redirection function until 1.50.
 - 2015/03/15 (1.36) - renamed style.TreeNodeSpacing to style.IndentSpacing, ImGuiStyleVar_TreeNodeSpacing to ImGuiStyleVar_IndentSpacing
 - 2015/03/13 (1.36) - renamed GetWindowIsFocused() to IsWindowFocused(). Kept inline redirection function until 1.50.
 - 2015/03/08 (1.35) - renamed style.ScrollBarWidth to style.ScrollbarWidth (casing)
 - 2015/02/27 (1.34) - renamed OpenNextNode(bool) to SetNextTreeNodeOpened(bool, ImGuiSetCond). Kept inline redirection function until 1.50.
 - 2015/02/27 (1.34) - renamed ImGuiSetCondition_*** to ImGuiSetCond_***, and _FirstUseThisSession becomes _Once.
 - 2015/02/11 (1.32) - changed text input callback ImGuiTextEditCallback return type from void-->int. reserved for future use, return 0 for now.
 - 2015/02/10 (1.32) - renamed GetItemWidth() to CalcItemWidth() to clarify its evolving behavior
 - 2015/02/08 (1.31) - renamed GetTextLineSpacing() to GetTextLineHeightWithSpacing()
 - 2015/02/01 (1.31) - removed IO.MemReallocFn (unused)
 - 2015/01/19 (1.30) - renamed ImGuiStorage::GetIntPtr()/GetFloatPtr() to GetIntRef()/GetIntRef() because Ptr was conflicting with actual pointer storage functions.
 - 2015/01/11 (1.30) - big font/image API change! now loads TTF file. allow for multiple fonts. no need for a PNG loader.
 - 2015/01/11 (1.30) - removed GetDefaultFontData(). uses io.Fonts->GetTextureData*() API to retrieve uncompressed pixels.
                       - old:  const void* png_data; unsigned int png_size; ImGui::GetDefaultFontData(NULL, NULL, &png_data, &png_size); [..Upload texture to GPU..];
                       - new:  unsigned char* pixels; int width, height; io.Fonts->GetTexDataAsRGBA32(&pixels, &width, &height); [..Upload texture to GPU..]; io.Fonts->SetTexID(YourTexIdentifier);
                       you now have more flexibility to load multiple TTF fonts and manage the texture buffer for internal needs. It is now recommended that you sample the font texture with bilinear interpolation.
 - 2015/01/11 (1.30) - added texture identifier in ImDrawCmd passed to your render function (we can now render images). make sure to call io.Fonts->SetTexID()
 - 2015/01/11 (1.30) - removed IO.PixelCenterOffset (unnecessary, can be handled in user projection matrix)
 - 2015/01/11 (1.30) - removed ImGui::IsItemFocused() in favor of ImGui::IsItemActive() which handles all widgets
 - 2014/12/10 (1.18) - removed SetNewWindowDefaultPos() in favor of new generic API SetNextWindowPos(pos, ImGuiSetCondition_FirstUseEver)
 - 2014/11/28 (1.17) - moved IO.Font*** options to inside the IO.Font-> structure (FontYOffset, FontTexUvForWhite, FontBaseScale, FontFallbackGlyph)
 - 2014/11/26 (1.17) - reworked syntax of IMGUI_ONCE_UPON_A_FRAME helper macro to increase compiler compatibility
 - 2014/11/07 (1.15) - renamed IsHovered() to IsItemHovered()
 - 2014/10/02 (1.14) - renamed IMGUI_INCLUDE_IMGUI_USER_CPP to IMGUI_INCLUDE_IMGUI_USER_INL and imgui_user.cpp to imgui_user.inl (more IDE friendly)
 - 2014/09/25 (1.13) - removed 'text_end' parameter from IO.SetClipboardTextFn (the string is now always zero-terminated for simplicity)
 - 2014/09/24 (1.12) - renamed SetFontScale() to SetWindowFontScale()
 - 2014/09/24 (1.12) - moved IM_MALLOC/IM_REALLOC/IM_FREE preprocessor defines to IO.MemAllocFn/IO.MemReallocFn/IO.MemFreeFn
 - 2014/08/30 (1.09) - removed IO.FontHeight (now computed automatically)
 - 2014/08/30 (1.09) - moved IMGUI_FONT_TEX_UV_FOR_WHITE preprocessor define to IO.FontTexUvForWhite
 - 2014/08/28 (1.09) - changed the behavior of IO.PixelCenterOffset following various rendering fixes


 FREQUENTLY ASKED QUESTIONS (FAQ)
 ================================

 Read all answers online:
   https://www.dearimgui.com/faq or https://github.com/ocornut/imgui/blob/master/docs/FAQ.md (same url)
 Read all answers locally (with a text editor or ideally a Markdown viewer):
   docs/FAQ.md
 Some answers are copied down here to facilitate searching in code.

 Q&A: Basics
 ===========

 Q: Where is the documentation?
 A: This library is poorly documented at the moment and expects the user to be acquainted with C/C++.
    - Run the examples/ applications and explore them.
    - Read Getting Started (https://github.com/ocornut/imgui/wiki/Getting-Started) guide.
    - See demo code in imgui_demo.cpp and particularly the ImGui::ShowDemoWindow() function.
    - The demo covers most features of Dear ImGui, so you can read the code and see its output.
    - See documentation and comments at the top of imgui.cpp + effectively imgui.h.
    - 20+ standalone example applications using e.g. OpenGL/DirectX are provided in the
      examples/ folder to explain how to integrate Dear ImGui with your own engine/application.
    - The Wiki (https://github.com/ocornut/imgui/wiki) has many resources and links.
    - The Glossary (https://github.com/ocornut/imgui/wiki/Glossary) page also may be useful.
    - Your programming IDE is your friend, find the type or function declaration to find comments
      associated with it.

 Q: What is this library called?
 Q: Which version should I get?
 >> This library is called "Dear ImGui", please don't call it "ImGui" :)
 >> See https://www.dearimgui.com/faq for details.

 Q&A: Integration
 ================

 Q: How to get started?
 A: Read https://github.com/ocornut/imgui/wiki/Getting-Started. Read 'PROGRAMMER GUIDE' above. Read examples/README.txt.

 Q: How can I tell whether to dispatch mouse/keyboard to Dear ImGui or my application?
 A: You should read the 'io.WantCaptureMouse', 'io.WantCaptureKeyboard' and 'io.WantTextInput' flags!
 >> See https://www.dearimgui.com/faq for a fully detailed answer. You really want to read this.

 Q. How can I enable keyboard or gamepad controls?
 Q: How can I use this on a machine without mouse, keyboard or screen? (input share, remote display)
 Q: I integrated Dear ImGui in my engine and little squares are showing instead of text...
 Q: I integrated Dear ImGui in my engine and some elements are clipping or disappearing when I move windows around...
 Q: I integrated Dear ImGui in my engine and some elements are displaying outside their expected windows boundaries...
 >> See https://www.dearimgui.com/faq

 Q&A: Usage
 ----------

 Q: About the ID Stack system..
   - Why is my widget not reacting when I click on it?
   - How can I have widgets with an empty label?
   - How can I have multiple widgets with the same label?
   - How can I have multiple windows with the same label?
 Q: How can I display an image? What is ImTextureID, how does it work?
 Q: How can I use my own math types instead of ImVec2?
 Q: How can I interact with standard C++ types (such as std::string and std::vector)?
 Q: How can I display custom shapes? (using low-level ImDrawList API)
 >> See https://www.dearimgui.com/faq

 Q&A: Fonts, Text
 ================

 Q: How should I handle DPI in my application?
 Q: How can I load a different font than the default?
 Q: How can I easily use icons in my application?
 Q: How can I load multiple fonts?
 Q: How can I display and input non-Latin characters such as Chinese, Japanese, Korean, Cyrillic?
 >> See https://www.dearimgui.com/faq and https://github.com/ocornut/imgui/edit/master/docs/FONTS.md

 Q&A: Concerns
 =============

 Q: Who uses Dear ImGui?
 Q: Can you create elaborate/serious tools with Dear ImGui?
 Q: Can you reskin the look of Dear ImGui?
 Q: Why using C++ (as opposed to C)?
 >> See https://www.dearimgui.com/faq

 Q&A: Community
 ==============

 Q: How can I help?
 A: - Businesses: please reach out to "omar AT dearimgui DOT com" if you work in a place using Dear ImGui!
      We can discuss ways for your company to fund development via invoiced technical support, maintenance or sponsoring contacts.
      This is among the most useful thing you can do for Dear ImGui. With increased funding, we sustain and grow work on this project.
      Also see https://github.com/ocornut/imgui/wiki/Sponsors
    - Businesses: you can also purchase licenses for the Dear ImGui Automation/Test Engine.
    - If you are experienced with Dear ImGui and C++, look at the GitHub issues, look at the Wiki, and see how you want to help and can help!
    - Disclose your usage of Dear ImGui via a dev blog post, a tweet, a screenshot, a mention somewhere etc.
      You may post screenshot or links in the gallery threads. Visuals are ideal as they inspire other programmers.
      But even without visuals, disclosing your use of dear imgui helps the library grow credibility, and help other teams and programmers with taking decisions.
    - If you have issues or if you need to hack into the library, even if you don't expect any support it is useful that you share your issues (on GitHub or privately).

*/

//-------------------------------------------------------------------------
// [SECTION] INCLUDES
//-------------------------------------------------------------------------

#if defined(_MSC_VER) && !defined(_CRT_SECURE_NO_WARNINGS)
#define _CRT_SECURE_NO_WARNINGS
#endif

#ifndef IMGUI_DEFINE_MATH_OPERATORS
#define IMGUI_DEFINE_MATH_OPERATORS
#endif

#include "imgui.h"
#ifndef IMGUI_DISABLE
#include "imgui_internal.h"

// System includes
#include <stdio.h>      // vsnprintf, sscanf, printf
#include <stdint.h>     // intptr_t

// [Windows] On non-Visual Studio compilers, we default to IMGUI_DISABLE_WIN32_DEFAULT_IME_FUNCTIONS unless explicitly enabled
#if defined(_WIN32) && !defined(_MSC_VER) && !defined(IMGUI_ENABLE_WIN32_DEFAULT_IME_FUNCTIONS) && !defined(IMGUI_DISABLE_WIN32_DEFAULT_IME_FUNCTIONS)
#define IMGUI_DISABLE_WIN32_DEFAULT_IME_FUNCTIONS
#endif

// [Windows] OS specific includes (optional)
#if defined(_WIN32) && defined(IMGUI_DISABLE_DEFAULT_FILE_FUNCTIONS) && defined(IMGUI_DISABLE_WIN32_DEFAULT_CLIPBOARD_FUNCTIONS) && defined(IMGUI_DISABLE_WIN32_DEFAULT_IME_FUNCTIONS) && !defined(IMGUI_DISABLE_WIN32_FUNCTIONS)
#define IMGUI_DISABLE_WIN32_FUNCTIONS
#endif
#if defined(_WIN32) && !defined(IMGUI_DISABLE_WIN32_FUNCTIONS)
#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif
#ifndef NOMINMAX
#define NOMINMAX
#endif
#ifndef __MINGW32__
#include <Windows.h>        // _wfopen, OpenClipboard
#else
#include <windows.h>
#endif
#if defined(WINAPI_FAMILY) && (WINAPI_FAMILY == WINAPI_FAMILY_APP) // UWP doesn't have all Win32 functions
#define IMGUI_DISABLE_WIN32_DEFAULT_CLIPBOARD_FUNCTIONS
#define IMGUI_DISABLE_WIN32_DEFAULT_IME_FUNCTIONS
#endif
#endif

// [Apple] OS specific includes
#if defined(__APPLE__)
#include <TargetConditionals.h>
#endif

// Visual Studio warnings
#ifdef _MSC_VER
#pragma warning (disable: 4127)             // condition expression is constant
#pragma warning (disable: 4996)             // 'This function or variable may be unsafe': strcpy, strdup, sprintf, vsnprintf, sscanf, fopen
#if defined(_MSC_VER) && _MSC_VER >= 1922   // MSVC 2019 16.2 or later
#pragma warning (disable: 5054)             // operator '|': deprecated between enumerations of different types
#endif
#pragma warning (disable: 26451)            // [Static Analyzer] Arithmetic overflow : Using operator 'xxx' on a 4 byte value and then casting the result to an 8 byte value. Cast the value to the wider type before calling operator 'xxx' to avoid overflow(io.2).
#pragma warning (disable: 26495)            // [Static Analyzer] Variable 'XXX' is uninitialized. Always initialize a member variable (type.6).
#pragma warning (disable: 26812)            // [Static Analyzer] The enum type 'xxx' is unscoped. Prefer 'enum class' over 'enum' (Enum.3).
#endif

// Clang/GCC warnings with -Weverything
#if defined(__clang__)
#if __has_warning("-Wunknown-warning-option")
#pragma clang diagnostic ignored "-Wunknown-warning-option"         // warning: unknown warning group 'xxx'                      // not all warnings are known by all Clang versions and they tend to be rename-happy.. so ignoring warnings triggers new warnings on some configuration. Great!
#endif
#pragma clang diagnostic ignored "-Wunknown-pragmas"                // warning: unknown warning group 'xxx'
#pragma clang diagnostic ignored "-Wold-style-cast"                 // warning: use of old-style cast                            // yes, they are more terse.
#pragma clang diagnostic ignored "-Wfloat-equal"                    // warning: comparing floating point with == or != is unsafe // storing and comparing against same constants (typically 0.0f) is ok.
#pragma clang diagnostic ignored "-Wformat-nonliteral"              // warning: format string is not a string literal            // passing non-literal to vsnformat(). yes, user passing incorrect format strings can crash the code.
#pragma clang diagnostic ignored "-Wexit-time-destructors"          // warning: declaration requires an exit-time destructor     // exit-time destruction order is undefined. if MemFree() leads to users code that has been disabled before exit it might cause problems. ImGui coding style welcomes static/globals.
#pragma clang diagnostic ignored "-Wglobal-constructors"            // warning: declaration requires a global destructor         // similar to above, not sure what the exact difference is.
#pragma clang diagnostic ignored "-Wsign-conversion"                // warning: implicit conversion changes signedness
#pragma clang diagnostic ignored "-Wformat-pedantic"                // warning: format specifies type 'void *' but the argument has type 'xxxx *' // unreasonable, would lead to casting every %p arg to void*. probably enabled by -pedantic.
#pragma clang diagnostic ignored "-Wint-to-void-pointer-cast"       // warning: cast to 'void *' from smaller integer type 'int'
#pragma clang diagnostic ignored "-Wzero-as-null-pointer-constant"  // warning: zero as null pointer constant                    // some standard header variations use #define NULL 0
#pragma clang diagnostic ignored "-Wdouble-promotion"               // warning: implicit conversion from 'float' to 'double' when passing argument to function  // using printf() is a misery with this as C++ va_arg ellipsis changes float to double.
#pragma clang diagnostic ignored "-Wimplicit-int-float-conversion"  // warning: implicit conversion from 'xxx' to 'float' may lose precision
#elif defined(__GNUC__)
// We disable -Wpragmas because GCC doesn't provide a has_warning equivalent and some forks/patches may not follow the warning/version association.
#pragma GCC diagnostic ignored "-Wpragmas"                  // warning: unknown option after '#pragma GCC diagnostic' kind
#pragma GCC diagnostic ignored "-Wunused-function"          // warning: 'xxxx' defined but not used
#pragma GCC diagnostic ignored "-Wint-to-pointer-cast"      // warning: cast to pointer from integer of different size
#pragma GCC diagnostic ignored "-Wformat"                   // warning: format '%p' expects argument of type 'void*', but argument 6 has type 'ImGuiWindow*'
#pragma GCC diagnostic ignored "-Wdouble-promotion"         // warning: implicit conversion from 'float' to 'double' when passing argument to function
#pragma GCC diagnostic ignored "-Wconversion"               // warning: conversion to 'xxxx' from 'xxxx' may alter its value
#pragma GCC diagnostic ignored "-Wformat-nonliteral"        // warning: format not a string literal, format string not checked
#pragma GCC diagnostic ignored "-Wstrict-overflow"          // warning: assuming signed overflow does not occur when assuming that (X - c) > X is always false
#pragma GCC diagnostic ignored "-Wclass-memaccess"          // [__GNUC__ >= 8] warning: 'memset/memcpy' clearing/writing an object of type 'xxxx' with no trivial copy-assignment; use assignment or value-initialization instead
#endif

// Debug options
#define IMGUI_DEBUG_NAV_SCORING     0   // Display navigation scoring preview when hovering items. Display last moving direction matches when holding CTRL
#define IMGUI_DEBUG_NAV_RECTS       0   // Display the reference navigation rectangle for each window

// When using CTRL+TAB (or Gamepad Square+L/R) we delay the visual a little in order to reduce visual noise doing a fast switch.
static const float NAV_WINDOWING_HIGHLIGHT_DELAY            = 0.20f;    // Time before the highlight and screen dimming starts fading in
static const float NAV_WINDOWING_LIST_APPEAR_DELAY          = 0.15f;    // Time before the window list starts to appear

// Window resizing from edges (when io.ConfigWindowsResizeFromEdges = true and ImGuiBackendFlags_HasMouseCursors is set in io.BackendFlags by backend)
static const float WINDOWS_HOVER_PADDING                    = 4.0f;     // Extend outside window for hovering/resizing (maxxed with TouchPadding) and inside windows for borders. Affect FindHoveredWindow().
static const float WINDOWS_RESIZE_FROM_EDGES_FEEDBACK_TIMER = 0.04f;    // Reduce visual noise by only highlighting the border after a certain time.
static const float WINDOWS_MOUSE_WHEEL_SCROLL_LOCK_TIMER    = 0.70f;    // Lock scrolled window (so it doesn't pick child windows that are scrolling through) for a certain time, unless mouse moved.

// Tooltip offset
static const ImVec2 TOOLTIP_DEFAULT_OFFSET = ImVec2(16, 10);            // Multiplied by g.Style.MouseCursorScale

// Docking
static const float DOCKING_TRANSPARENT_PAYLOAD_ALPHA        = 0.50f;    // For use with io.ConfigDockingTransparentPayload. Apply to Viewport _or_ WindowBg in host viewport.

//-------------------------------------------------------------------------
// [SECTION] FORWARD DECLARATIONS
//-------------------------------------------------------------------------

static void             SetCurrentWindow(ImGuiWindow* window);
static void             FindHoveredWindow();
static ImGuiWindow*     CreateNewWindow(const char* name, ImGuiWindowFlags flags);
static ImVec2           CalcNextScrollFromScrollTargetAndClamp(ImGuiWindow* window);

static void             AddWindowToSortBuffer(ImVector<ImGuiWindow*>* out_sorted_windows, ImGuiWindow* window);

// Settings
static void             WindowSettingsHandler_ClearAll(ImGuiContext*, ImGuiSettingsHandler*);
static void*            WindowSettingsHandler_ReadOpen(ImGuiContext*, ImGuiSettingsHandler*, const char* name);
static void             WindowSettingsHandler_ReadLine(ImGuiContext*, ImGuiSettingsHandler*, void* entry, const char* line);
static void             WindowSettingsHandler_ApplyAll(ImGuiContext*, ImGuiSettingsHandler*);
static void             WindowSettingsHandler_WriteAll(ImGuiContext*, ImGuiSettingsHandler*, ImGuiTextBuffer* buf);

// Platform Dependents default implementation for IO functions
static const char*      GetClipboardTextFn_DefaultImpl(void* user_data_ctx);
static void             SetClipboardTextFn_DefaultImpl(void* user_data_ctx, const char* text);
static void             SetPlatformImeDataFn_DefaultImpl(ImGuiViewport* viewport, ImGuiPlatformImeData* data);

namespace ImGui
{
// Navigation
static void             NavUpdate();
static void             NavUpdateWindowing();
static void             NavUpdateWindowingOverlay();
static void             NavUpdateCancelRequest();
static void             NavUpdateCreateMoveRequest();
static void             NavUpdateCreateTabbingRequest();
static float            NavUpdatePageUpPageDown();
static inline void      NavUpdateAnyRequestFlag();
static void             NavUpdateCreateWrappingRequest();
static void             NavEndFrame();
static bool             NavScoreItem(ImGuiNavItemData* result);
static void             NavApplyItemToResult(ImGuiNavItemData* result);
static void             NavProcessItem();
static void             NavProcessItemForTabbingRequest(ImGuiID id, ImGuiItemFlags item_flags, ImGuiNavMoveFlags move_flags);
static ImVec2           NavCalcPreferredRefPos();
static void             NavSaveLastChildNavWindowIntoParent(ImGuiWindow* nav_window);
static ImGuiWindow*     NavRestoreLastChildNavWindow(ImGuiWindow* window);
static void             NavRestoreLayer(ImGuiNavLayer layer);
static int              FindWindowFocusIndex(ImGuiWindow* window);

// Error Checking and Debug Tools
static void             ErrorCheckNewFrameSanityChecks();
static void             ErrorCheckEndFrameSanityChecks();
static void             UpdateDebugToolItemPicker();
static void             UpdateDebugToolStackQueries();

// Inputs
static void             UpdateKeyboardInputs();
static void             UpdateMouseInputs();
static void             UpdateMouseWheel();
static void             UpdateKeyRoutingTable(ImGuiKeyRoutingTable* rt);

// Misc
static void             UpdateSettings();
static int              UpdateWindowManualResize(ImGuiWindow* window, const ImVec2& size_auto_fit, int* border_hovered, int* border_held, int resize_grip_count, ImU32 resize_grip_col[4], const ImRect& visibility_rect);
static void             RenderWindowOuterBorders(ImGuiWindow* window);
static void             RenderWindowDecorations(ImGuiWindow* window, const ImRect& title_bar_rect, bool title_bar_is_highlight, bool handle_borders_and_resize_grips, int resize_grip_count, const ImU32 resize_grip_col[4], float resize_grip_draw_size);
static void             RenderWindowTitleBarContents(ImGuiWindow* window, const ImRect& title_bar_rect, const char* name, bool* p_open);
static void             RenderDimmedBackgroundBehindWindow(ImGuiWindow* window, ImU32 col);
static void             RenderDimmedBackgrounds();

// Viewports
const ImGuiID           IMGUI_VIEWPORT_DEFAULT_ID = 0x11111111; // Using an arbitrary constant instead of e.g. ImHashStr("ViewportDefault", 0); so it's easier to spot in the debugger. The exact value doesn't matter.
static ImGuiViewportP*  AddUpdateViewport(ImGuiWindow* window, ImGuiID id, const ImVec2& platform_pos, const ImVec2& size, ImGuiViewportFlags flags);
static void             DestroyViewport(ImGuiViewportP* viewport);
static void             UpdateViewportsNewFrame();
static void             UpdateViewportsEndFrame();
static void             WindowSelectViewport(ImGuiWindow* window);
static void             WindowSyncOwnedViewport(ImGuiWindow* window, ImGuiWindow* parent_window_in_stack);
static bool             UpdateTryMergeWindowIntoHostViewport(ImGuiWindow* window, ImGuiViewportP* host_viewport);
static bool             UpdateTryMergeWindowIntoHostViewports(ImGuiWindow* window);
static bool             GetWindowAlwaysWantOwnViewport(ImGuiWindow* window);
static int              FindPlatformMonitorForPos(const ImVec2& pos);
static int              FindPlatformMonitorForRect(const ImRect& r);
static void             UpdateViewportPlatformMonitor(ImGuiViewportP* viewport);

}

//-----------------------------------------------------------------------------
// [SECTION] CONTEXT AND MEMORY ALLOCATORS
//-----------------------------------------------------------------------------

// DLL users:
// - Heaps and globals are not shared across DLL boundaries!
// - You will need to call SetCurrentContext() + SetAllocatorFunctions() for each static/DLL boundary you are calling from.
// - Same applies for hot-reloading mechanisms that are reliant on reloading DLL (note that many hot-reloading mechanisms work without DLL).
// - Using Dear ImGui via a shared library is not recommended, because of function call overhead and because we don't guarantee backward nor forward ABI compatibility.
// - Confused? In a debugger: add GImGui to your watch window and notice how its value changes depending on your current location (which DLL boundary you are in).

// Current context pointer. Implicitly used by all Dear ImGui functions. Always assumed to be != NULL.
// - ImGui::CreateContext() will automatically set this pointer if it is NULL.
//   Change to a different context by calling ImGui::SetCurrentContext().
// - Important: Dear ImGui functions are not thread-safe because of this pointer.
//   If you want thread-safety to allow N threads to access N different contexts:
//   - Change this variable to use thread local storage so each thread can refer to a different context, in your imconfig.h:
//         struct ImGuiContext;
//         extern thread_local ImGuiContext* MyImGuiTLS;
//         #define GImGui MyImGuiTLS
//     And then define MyImGuiTLS in one of your cpp files. Note that thread_local is a C++11 keyword, earlier C++ uses compiler-specific keyword.
//   - Future development aims to make this context pointer explicit to all calls. Also read https://github.com/ocornut/imgui/issues/586
//   - If you need a finite number of contexts, you may compile and use multiple instances of the ImGui code from a different namespace.
// - DLL users: read comments above.
#ifndef GImGui
ImGuiContext*   GImGui = NULL;
#endif

// Memory Allocator functions. Use SetAllocatorFunctions() to change them.
// - You probably don't want to modify that mid-program, and if you use global/static e.g. ImVector<> instances you may need to keep them accessible during program destruction.
// - DLL users: read comments above.
#ifndef IMGUI_DISABLE_DEFAULT_ALLOCATORS
static void*   MallocWrapper(size_t size, void* user_data)    { IM_UNUSED(user_data); return malloc(size); }
static void    FreeWrapper(void* ptr, void* user_data)        { IM_UNUSED(user_data); free(ptr); }
#else
static void*   MallocWrapper(size_t size, void* user_data)    { IM_UNUSED(user_data); IM_UNUSED(size); IM_ASSERT(0); return NULL; }
static void    FreeWrapper(void* ptr, void* user_data)        { IM_UNUSED(user_data); IM_UNUSED(ptr); IM_ASSERT(0); }
#endif
static ImGuiMemAllocFunc    GImAllocatorAllocFunc = MallocWrapper;
static ImGuiMemFreeFunc     GImAllocatorFreeFunc = FreeWrapper;
static void*                GImAllocatorUserData = NULL;

//-----------------------------------------------------------------------------
// [SECTION] USER FACING STRUCTURES (ImGuiStyle, ImGuiIO)
//-----------------------------------------------------------------------------

ImGuiStyle::ImGuiStyle()
{
    Alpha                   = 1.0f;             // Global alpha applies to everything in Dear ImGui.
    DisabledAlpha           = 0.60f;            // Additional alpha multiplier applied by BeginDisabled(). Multiply over current value of Alpha.
    WindowPadding           = ImVec2(8,8);      // Padding within a window
    WindowRounding          = 0.0f;             // Radius of window corners rounding. Set to 0.0f to have rectangular windows. Large values tend to lead to variety of artifacts and are not recommended.
    WindowBorderSize        = 1.0f;             // Thickness of border around windows. Generally set to 0.0f or 1.0f. Other values not well tested.
    WindowMinSize           = ImVec2(32,32);    // Minimum window size
    WindowTitleAlign        = ImVec2(0.0f,0.5f);// Alignment for title bar text
    WindowMenuButtonPosition= ImGuiDir_Left;    // Position of the collapsing/docking button in the title bar (left/right). Defaults to ImGuiDir_Left.
    ChildRounding           = 0.0f;             // Radius of child window corners rounding. Set to 0.0f to have rectangular child windows
    ChildBorderSize         = 1.0f;             // Thickness of border around child windows. Generally set to 0.0f or 1.0f. Other values not well tested.
    PopupRounding           = 0.0f;             // Radius of popup window corners rounding. Set to 0.0f to have rectangular child windows
    PopupBorderSize         = 1.0f;             // Thickness of border around popup or tooltip windows. Generally set to 0.0f or 1.0f. Other values not well tested.
    FramePadding            = ImVec2(4,3);      // Padding within a framed rectangle (used by most widgets)
    FrameRounding           = 0.0f;             // Radius of frame corners rounding. Set to 0.0f to have rectangular frames (used by most widgets).
    FrameBorderSize         = 0.0f;             // Thickness of border around frames. Generally set to 0.0f or 1.0f. Other values not well tested.
    ItemSpacing             = ImVec2(8,4);      // Horizontal and vertical spacing between widgets/lines
    ItemInnerSpacing        = ImVec2(4,4);      // Horizontal and vertical spacing between within elements of a composed widget (e.g. a slider and its label)
    CellPadding             = ImVec2(4,2);      // Padding within a table cell. CellPadding.y may be altered between different rows.
    TouchExtraPadding       = ImVec2(0,0);      // Expand reactive bounding box for touch-based system where touch position is not accurate enough. Unfortunately we don't sort widgets so priority on overlap will always be given to the first widget. So don't grow this too much!
    IndentSpacing           = 21.0f;            // Horizontal spacing when e.g. entering a tree node. Generally == (FontSize + FramePadding.x*2).
    ColumnsMinSpacing       = 6.0f;             // Minimum horizontal spacing between two columns. Preferably > (FramePadding.x + 1).
    ScrollbarSize           = 14.0f;            // Width of the vertical scrollbar, Height of the horizontal scrollbar
    ScrollbarRounding       = 9.0f;             // Radius of grab corners rounding for scrollbar
    GrabMinSize             = 12.0f;            // Minimum width/height of a grab box for slider/scrollbar
    GrabRounding            = 0.0f;             // Radius of grabs corners rounding. Set to 0.0f to have rectangular slider grabs.
    LogSliderDeadzone       = 4.0f;             // The size in pixels of the dead-zone around zero on logarithmic sliders that cross zero.
    TabRounding             = 4.0f;             // Radius of upper corners of a tab. Set to 0.0f to have rectangular tabs.
    TabBorderSize           = 0.0f;             // Thickness of border around tabs.
    TabMinWidthForCloseButton = 0.0f;           // Minimum width for close button to appear on an unselected tab when hovered. Set to 0.0f to always show when hovering, set to FLT_MAX to never show close button unless selected.
    TabBarBorderSize        = 1.0f;             // Thickness of tab-bar separator, which takes on the tab active color to denote focus.
    TableAngledHeadersAngle = 35.0f * (IM_PI / 180.0f); // Angle of angled headers (supported values range from -50 degrees to +50 degrees).
    ColorButtonPosition     = ImGuiDir_Right;   // Side of the color button in the ColorEdit4 widget (left/right). Defaults to ImGuiDir_Right.
    ButtonTextAlign         = ImVec2(0.5f,0.5f);// Alignment of button text when button is larger than text.
    SelectableTextAlign     = ImVec2(0.0f,0.0f);// Alignment of selectable text. Defaults to (0.0f, 0.0f) (top-left aligned). It's generally important to keep this left-aligned if you want to lay multiple items on a same line.
    SeparatorTextBorderSize = 3.0f;             // Thickkness of border in SeparatorText()
    SeparatorTextAlign      = ImVec2(0.0f,0.5f);// Alignment of text within the separator. Defaults to (0.0f, 0.5f) (left aligned, center).
    SeparatorTextPadding    = ImVec2(20.0f,3.f);// Horizontal offset of text from each edge of the separator + spacing on other axis. Generally small values. .y is recommended to be == FramePadding.y.
    DisplayWindowPadding    = ImVec2(19,19);    // Window position are clamped to be visible within the display area or monitors by at least this amount. Only applies to regular windows.
    DisplaySafeAreaPadding  = ImVec2(3,3);      // If you cannot see the edge of your screen (e.g. on a TV) increase the safe area padding. Covers popups/tooltips as well regular windows.
    DockingSeparatorSize    = 2.0f;             // Thickness of resizing border between docked windows
    MouseCursorScale        = 1.0f;             // Scale software rendered mouse cursor (when io.MouseDrawCursor is enabled). May be removed later.
    AntiAliasedLines        = true;             // Enable anti-aliased lines/borders. Disable if you are really tight on CPU/GPU.
    AntiAliasedLinesUseTex  = true;             // Enable anti-aliased lines/borders using textures where possible. Require backend to render with bilinear filtering (NOT point/nearest filtering).
    AntiAliasedFill         = true;             // Enable anti-aliased filled shapes (rounded rectangles, circles, etc.).
    CurveTessellationTol    = 1.25f;            // Tessellation tolerance when using PathBezierCurveTo() without a specific number of segments. Decrease for highly tessellated curves (higher quality, more polygons), increase to reduce quality.
    CircleTessellationMaxError = 0.30f;         // Maximum error (in pixels) allowed when using AddCircle()/AddCircleFilled() or drawing rounded corner rectangles with no explicit segment count specified. Decrease for higher quality but more geometry.

    // Behaviors
    HoverStationaryDelay    = 0.15f;            // Delay for IsItemHovered(ImGuiHoveredFlags_Stationary). Time required to consider mouse stationary.
    HoverDelayShort         = 0.15f;            // Delay for IsItemHovered(ImGuiHoveredFlags_DelayShort). Usually used along with HoverStationaryDelay.
    HoverDelayNormal        = 0.40f;            // Delay for IsItemHovered(ImGuiHoveredFlags_DelayNormal). "
    HoverFlagsForTooltipMouse = ImGuiHoveredFlags_Stationary | ImGuiHoveredFlags_DelayShort | ImGuiHoveredFlags_AllowWhenDisabled;    // Default flags when using IsItemHovered(ImGuiHoveredFlags_ForTooltip) or BeginItemTooltip()/SetItemTooltip() while using mouse.
    HoverFlagsForTooltipNav = ImGuiHoveredFlags_NoSharedDelay | ImGuiHoveredFlags_DelayNormal | ImGuiHoveredFlags_AllowWhenDisabled;  // Default flags when using IsItemHovered(ImGuiHoveredFlags_ForTooltip) or BeginItemTooltip()/SetItemTooltip() while using keyboard/gamepad.

    // Default theme
    ImGui::StyleColorsDark(this);
}

// To scale your entire UI (e.g. if you want your app to use High DPI or generally be DPI aware) you may use this helper function. Scaling the fonts is done separately and is up to you.
// Important: This operation is lossy because we round all sizes to integer. If you need to change your scale multiples, call this over a freshly initialized ImGuiStyle structure rather than scaling multiple times.
void ImGuiStyle::ScaleAllSizes(float scale_factor)
{
    WindowPadding = ImTrunc(WindowPadding * scale_factor);
    WindowRounding = ImTrunc(WindowRounding * scale_factor);
    WindowMinSize = ImTrunc(WindowMinSize * scale_factor);
    ChildRounding = ImTrunc(ChildRounding * scale_factor);
    PopupRounding = ImTrunc(PopupRounding * scale_factor);
    FramePadding = ImTrunc(FramePadding * scale_factor);
    FrameRounding = ImTrunc(FrameRounding * scale_factor);
    ItemSpacing = ImTrunc(ItemSpacing * scale_factor);
    ItemInnerSpacing = ImTrunc(ItemInnerSpacing * scale_factor);
    CellPadding = ImTrunc(CellPadding * scale_factor);
    TouchExtraPadding = ImTrunc(TouchExtraPadding * scale_factor);
    IndentSpacing = ImTrunc(IndentSpacing * scale_factor);
    ColumnsMinSpacing = ImTrunc(ColumnsMinSpacing * scale_factor);
    ScrollbarSize = ImTrunc(ScrollbarSize * scale_factor);
    ScrollbarRounding = ImTrunc(ScrollbarRounding * scale_factor);
    GrabMinSize = ImTrunc(GrabMinSize * scale_factor);
    GrabRounding = ImTrunc(GrabRounding * scale_factor);
    LogSliderDeadzone = ImTrunc(LogSliderDeadzone * scale_factor);
    TabRounding = ImTrunc(TabRounding * scale_factor);
    TabMinWidthForCloseButton = (TabMinWidthForCloseButton != FLT_MAX) ? ImTrunc(TabMinWidthForCloseButton * scale_factor) : FLT_MAX;
    SeparatorTextPadding = ImTrunc(SeparatorTextPadding * scale_factor);
    DockingSeparatorSize = ImTrunc(DockingSeparatorSize * scale_factor);
    DisplayWindowPadding = ImTrunc(DisplayWindowPadding * scale_factor);
    DisplaySafeAreaPadding = ImTrunc(DisplaySafeAreaPadding * scale_factor);
    MouseCursorScale = ImTrunc(MouseCursorScale * scale_factor);
}

ImGuiIO::ImGuiIO()
{
    // Most fields are initialized with zero
    memset(this, 0, sizeof(*this));
    IM_STATIC_ASSERT(IM_ARRAYSIZE(ImGuiIO::MouseDown) == ImGuiMouseButton_COUNT && IM_ARRAYSIZE(ImGuiIO::MouseClicked) == ImGuiMouseButton_COUNT);

    // Settings
    ConfigFlags = ImGuiConfigFlags_None;
    BackendFlags = ImGuiBackendFlags_None;
    DisplaySize = ImVec2(-1.0f, -1.0f);
    DeltaTime = 1.0f / 60.0f;
    IniSavingRate = 5.0f;
    IniFilename = "imgui.ini"; // Important: "imgui.ini" is relative to current working dir, most apps will want to lock this to an absolute path (e.g. same path as executables).
    LogFilename = "imgui_log.txt";
#ifndef IMGUI_DISABLE_OBSOLETE_KEYIO
    for (int i = 0; i < ImGuiKey_COUNT; i++)
        KeyMap[i] = -1;
#endif
    UserData = NULL;

    Fonts = NULL;
    FontGlobalScale = 1.0f;
    FontDefault = NULL;
    FontAllowUserScaling = false;
    DisplayFramebufferScale = ImVec2(1.0f, 1.0f);

    // Docking options (when ImGuiConfigFlags_DockingEnable is set)
    ConfigDockingNoSplit = false;
    ConfigDockingWithShift = false;
    ConfigDockingAlwaysTabBar = false;
    ConfigDockingTransparentPayload = false;

    // Viewport options (when ImGuiConfigFlags_ViewportsEnable is set)
    ConfigViewportsNoAutoMerge = false;
    ConfigViewportsNoTaskBarIcon = false;
    ConfigViewportsNoDecoration = true;
    ConfigViewportsNoDefaultParent = false;

    // Miscellaneous options
    MouseDrawCursor = false;
#ifdef __APPLE__
    ConfigMacOSXBehaviors = true;  // Set Mac OS X style defaults based on __APPLE__ compile time flag
#else
    ConfigMacOSXBehaviors = false;
#endif
    ConfigInputTrickleEventQueue = true;
    ConfigInputTextCursorBlink = true;
    ConfigInputTextEnterKeepActive = false;
    ConfigDragClickToInputText = false;
    ConfigWindowsResizeFromEdges = true;
    ConfigWindowsMoveFromTitleBarOnly = false;
    ConfigMemoryCompactTimer = 60.0f;
    ConfigDebugBeginReturnValueOnce = false;
    ConfigDebugBeginReturnValueLoop = false;

    // Inputs Behaviors
    MouseDoubleClickTime = 0.30f;
    MouseDoubleClickMaxDist = 6.0f;
    MouseDragThreshold = 6.0f;
    KeyRepeatDelay = 0.275f;
    KeyRepeatRate = 0.050f;

    // Platform Functions
    // Note: Initialize() will setup default clipboard/ime handlers.
    BackendPlatformName = BackendRendererName = NULL;
    BackendPlatformUserData = BackendRendererUserData = BackendLanguageUserData = NULL;
    PlatformLocaleDecimalPoint = '.';

    // Input (NB: we already have memset zero the entire structure!)
    MousePos = ImVec2(-FLT_MAX, -FLT_MAX);
    MousePosPrev = ImVec2(-FLT_MAX, -FLT_MAX);
    MouseSource = ImGuiMouseSource_Mouse;
    for (int i = 0; i < IM_ARRAYSIZE(MouseDownDuration); i++) MouseDownDuration[i] = MouseDownDurationPrev[i] = -1.0f;
    for (int i = 0; i < IM_ARRAYSIZE(KeysData); i++) { KeysData[i].DownDuration = KeysData[i].DownDurationPrev = -1.0f; }
    AppAcceptingEvents = true;
    BackendUsingLegacyKeyArrays = (ImS8)-1;
    BackendUsingLegacyNavInputArray = true; // assume using legacy array until proven wrong
}

// Pass in translated ASCII characters for text input.
// - with glfw you can get those from the callback set in glfwSetCharCallback()
// - on Windows you can get those using ToAscii+keyboard state, or via the WM_CHAR message
// FIXME: Should in theory be called "AddCharacterEvent()" to be consistent with new API
void ImGuiIO::AddInputCharacter(unsigned int c)
{
    IM_ASSERT(Ctx != NULL);
    ImGuiContext& g = *Ctx;
    if (c == 0 || !AppAcceptingEvents)
        return;

    ImGuiInputEvent e;
    e.Type = ImGuiInputEventType_Text;
    e.Source = ImGuiInputSource_Keyboard;
    e.EventId = g.InputEventsNextEventId++;
    e.Text.Char = c;
    g.InputEventsQueue.push_back(e);
}

// UTF16 strings use surrogate pairs to encode codepoints >= 0x10000, so
// we should save the high surrogate.
void ImGuiIO::AddInputCharacterUTF16(ImWchar16 c)
{
    if ((c == 0 && InputQueueSurrogate == 0) || !AppAcceptingEvents)
        return;

    if ((c & 0xFC00) == 0xD800) // High surrogate, must save
    {
        if (InputQueueSurrogate != 0)
            AddInputCharacter(IM_UNICODE_CODEPOINT_INVALID);
        InputQueueSurrogate = c;
        return;
    }

    ImWchar cp = c;
    if (InputQueueSurrogate != 0)
    {
        if ((c & 0xFC00) != 0xDC00) // Invalid low surrogate
        {
            AddInputCharacter(IM_UNICODE_CODEPOINT_INVALID);
        }
        else
        {
#if IM_UNICODE_CODEPOINT_MAX == 0xFFFF
            cp = IM_UNICODE_CODEPOINT_INVALID; // Codepoint will not fit in ImWchar
#else
            cp = (ImWchar)(((InputQueueSurrogate - 0xD800) << 10) + (c - 0xDC00) + 0x10000);
#endif
        }

        InputQueueSurrogate = 0;
    }
    AddInputCharacter((unsigned)cp);
}

void ImGuiIO::AddInputCharactersUTF8(const char* utf8_chars)
{
    if (!AppAcceptingEvents)
        return;
    while (*utf8_chars != 0)
    {
        unsigned int c = 0;
        utf8_chars += ImTextCharFromUtf8(&c, utf8_chars, NULL);
        AddInputCharacter(c);
    }
}

// Clear all incoming events.
void ImGuiIO::ClearEventsQueue()
{
    IM_ASSERT(Ctx != NULL);
    ImGuiContext& g = *Ctx;
    g.InputEventsQueue.clear();
}

// Clear current keyboard/mouse/gamepad state + current frame text input buffer. Equivalent to releasing all keys/buttons.
void ImGuiIO::ClearInputKeys()
{
#ifndef IMGUI_DISABLE_OBSOLETE_KEYIO
    memset(KeysDown, 0, sizeof(KeysDown));
#endif
    for (int n = 0; n < IM_ARRAYSIZE(KeysData); n++)
    {
        KeysData[n].Down             = false;
        KeysData[n].DownDuration     = -1.0f;
        KeysData[n].DownDurationPrev = -1.0f;
    }
    KeyCtrl = KeyShift = KeyAlt = KeySuper = false;
    KeyMods = ImGuiMod_None;
    MousePos = ImVec2(-FLT_MAX, -FLT_MAX);
    for (int n = 0; n < IM_ARRAYSIZE(MouseDown); n++)
    {
        MouseDown[n] = false;
        MouseDownDuration[n] = MouseDownDurationPrev[n] = -1.0f;
    }
    MouseWheel = MouseWheelH = 0.0f;
    InputQueueCharacters.resize(0); // Behavior of old ClearInputCharacters().
}

// Removed this as it is ambiguous/misleading and generally incorrect to use with the existence of a higher-level input queue.
// Current frame character buffer is now also cleared by ClearInputKeys().
#ifndef IMGUI_DISABLE_OBSOLETE_FUNCTIONS
void ImGuiIO::ClearInputCharacters()
{
    InputQueueCharacters.resize(0);
}
#endif

static ImGuiInputEvent* FindLatestInputEvent(ImGuiContext* ctx, ImGuiInputEventType type, int arg = -1)
{
    ImGuiContext& g = *ctx;
    for (int n = g.InputEventsQueue.Size - 1; n >= 0; n--)
    {
        ImGuiInputEvent* e = &g.InputEventsQueue[n];
        if (e->Type != type)
            continue;
        if (type == ImGuiInputEventType_Key && e->Key.Key != arg)
            continue;
        if (type == ImGuiInputEventType_MouseButton && e->MouseButton.Button != arg)
            continue;
        return e;
    }
    return NULL;
}

// Queue a new key down/up event.
// - ImGuiKey key:       Translated key (as in, generally ImGuiKey_A matches the key end-user would use to emit an 'A' character)
// - bool down:          Is the key down? use false to signify a key release.
// - float analog_value: 0.0f..1.0f
// IMPORTANT: THIS FUNCTION AND OTHER "ADD" GRABS THE CONTEXT FROM OUR INSTANCE.
// WE NEED TO ENSURE THAT ALL FUNCTION CALLS ARE FULLFILLING THIS, WHICH IS WHY GetKeyData() HAS AN EXPLICIT CONTEXT.
void ImGuiIO::AddKeyAnalogEvent(ImGuiKey key, bool down, float analog_value)
{
    //if (e->Down) { IMGUI_DEBUG_LOG_IO("AddKeyEvent() Key='%s' %d, NativeKeycode = %d, NativeScancode = %d\n", ImGui::GetKeyName(e->Key), e->Down, e->NativeKeycode, e->NativeScancode); }
    IM_ASSERT(Ctx != NULL);
    if (key == ImGuiKey_None || !AppAcceptingEvents)
        return;
    ImGuiContext& g = *Ctx;
    IM_ASSERT(ImGui::IsNamedKeyOrModKey(key)); // Backend needs to pass a valid ImGuiKey_ constant. 0..511 values are legacy native key codes which are not accepted by this API.
    IM_ASSERT(ImGui::IsAliasKey(key) == false); // Backend cannot submit ImGuiKey_MouseXXX values they are automatically inferred from AddMouseXXX() events.
    IM_ASSERT(key != ImGuiMod_Shortcut); // We could easily support the translation here but it seems saner to not accept it (TestEngine perform a translation itself)

    // Verify that backend isn't mixing up using new io.AddKeyEvent() api and old io.KeysDown[] + io.KeyMap[] data.
#ifndef IMGUI_DISABLE_OBSOLETE_KEYIO
    IM_ASSERT((BackendUsingLegacyKeyArrays == -1 || BackendUsingLegacyKeyArrays == 0) && "Backend needs to either only use io.AddKeyEvent(), either only fill legacy io.KeysDown[] + io.KeyMap[]. Not both!");
    if (BackendUsingLegacyKeyArrays == -1)
        for (int n = ImGuiKey_NamedKey_BEGIN; n < ImGuiKey_NamedKey_END; n++)
            IM_ASSERT(KeyMap[n] == -1 && "Backend needs to either only use io.AddKeyEvent(), either only fill legacy io.KeysDown[] + io.KeyMap[]. Not both!");
    BackendUsingLegacyKeyArrays = 0;
#endif
    if (ImGui::IsGamepadKey(key))
        BackendUsingLegacyNavInputArray = false;

    // Filter duplicate (in particular: key mods and gamepad analog values are commonly spammed)
    const ImGuiInputEvent* latest_event = FindLatestInputEvent(&g, ImGuiInputEventType_Key, (int)key);
    const ImGuiKeyData* key_data = ImGui::GetKeyData(&g, key);
    const bool latest_key_down = latest_event ? latest_event->Key.Down : key_data->Down;
    const float latest_key_analog = latest_event ? latest_event->Key.AnalogValue : key_data->AnalogValue;
    if (latest_key_down == down && latest_key_analog == analog_value)
        return;

    // Add event
    ImGuiInputEvent e;
    e.Type = ImGuiInputEventType_Key;
    e.Source = ImGui::IsGamepadKey(key) ? ImGuiInputSource_Gamepad : ImGuiInputSource_Keyboard;
    e.EventId = g.InputEventsNextEventId++;
    e.Key.Key = key;
    e.Key.Down = down;
    e.Key.AnalogValue = analog_value;
    g.InputEventsQueue.push_back(e);
}

void ImGuiIO::AddKeyEvent(ImGuiKey key, bool down)
{
    if (!AppAcceptingEvents)
        return;
    AddKeyAnalogEvent(key, down, down ? 1.0f : 0.0f);
}

// [Optional] Call after AddKeyEvent().
// Specify native keycode, scancode + Specify index for legacy <1.87 IsKeyXXX() functions with native indices.
// If you are writing a backend in 2022 or don't use IsKeyXXX() with native values that are not ImGuiKey values, you can avoid calling this.
void ImGuiIO::SetKeyEventNativeData(ImGuiKey key, int native_keycode, int native_scancode, int native_legacy_index)
{
    if (key == ImGuiKey_None)
        return;
    IM_ASSERT(ImGui::IsNamedKey(key)); // >= 512
    IM_ASSERT(native_legacy_index == -1 || ImGui::IsLegacyKey((ImGuiKey)native_legacy_index)); // >= 0 && <= 511
    IM_UNUSED(native_keycode);  // Yet unused
    IM_UNUSED(native_scancode); // Yet unused

    // Build native->imgui map so old user code can still call key functions with native 0..511 values.
#ifndef IMGUI_DISABLE_OBSOLETE_KEYIO
    const int legacy_key = (native_legacy_index != -1) ? native_legacy_index : native_keycode;
    if (!ImGui::IsLegacyKey((ImGuiKey)legacy_key))
        return;
    KeyMap[legacy_key] = key;
    KeyMap[key] = legacy_key;
#else
    IM_UNUSED(key);
    IM_UNUSED(native_legacy_index);
#endif
}

// Set master flag for accepting key/mouse/text events (default to true). Useful if you have native dialog boxes that are interrupting your application loop/refresh, and you want to disable events being queued while your app is frozen.
void ImGuiIO::SetAppAcceptingEvents(bool accepting_events)
{
    AppAcceptingEvents = accepting_events;
}

// Queue a mouse move event
void ImGuiIO::AddMousePosEvent(float x, float y)
{
    IM_ASSERT(Ctx != NULL);
    ImGuiContext& g = *Ctx;
    if (!AppAcceptingEvents)
        return;

    // Apply same flooring as UpdateMouseInputs()
    ImVec2 pos((x > -FLT_MAX) ? ImFloor(x) : x, (y > -FLT_MAX) ? ImFloor(y) : y);

    // Filter duplicate
    const ImGuiInputEvent* latest_event = FindLatestInputEvent(&g, ImGuiInputEventType_MousePos);
    const ImVec2 latest_pos = latest_event ? ImVec2(latest_event->MousePos.PosX, latest_event->MousePos.PosY) : g.IO.MousePos;
    if (latest_pos.x == pos.x && latest_pos.y == pos.y)
        return;

    ImGuiInputEvent e;
    e.Type = ImGuiInputEventType_MousePos;
    e.Source = ImGuiInputSource_Mouse;
    e.EventId = g.InputEventsNextEventId++;
    e.MousePos.PosX = pos.x;
    e.MousePos.PosY = pos.y;
    e.MousePos.MouseSource = g.InputEventsNextMouseSource;
    g.InputEventsQueue.push_back(e);
}

void ImGuiIO::AddMouseButtonEvent(int mouse_button, bool down)
{
    IM_ASSERT(Ctx != NULL);
    ImGuiContext& g = *Ctx;
    IM_ASSERT(mouse_button >= 0 && mouse_button < ImGuiMouseButton_COUNT);
    if (!AppAcceptingEvents)
        return;

    // Filter duplicate
    const ImGuiInputEvent* latest_event = FindLatestInputEvent(&g, ImGuiInputEventType_MouseButton, (int)mouse_button);
    const bool latest_button_down = latest_event ? latest_event->MouseButton.Down : g.IO.MouseDown[mouse_button];
    if (latest_button_down == down)
        return;

    ImGuiInputEvent e;
    e.Type = ImGuiInputEventType_MouseButton;
    e.Source = ImGuiInputSource_Mouse;
    e.EventId = g.InputEventsNextEventId++;
    e.MouseButton.Button = mouse_button;
    e.MouseButton.Down = down;
    e.MouseButton.MouseSource = g.InputEventsNextMouseSource;
    g.InputEventsQueue.push_back(e);
}

// Queue a mouse wheel event (some mouse/API may only have a Y component)
void ImGuiIO::AddMouseWheelEvent(float wheel_x, float wheel_y)
{
    IM_ASSERT(Ctx != NULL);
    ImGuiContext& g = *Ctx;

    // Filter duplicate (unlike most events, wheel values are relative and easy to filter)
    if (!AppAcceptingEvents || (wheel_x == 0.0f && wheel_y == 0.0f))
        return;

    ImGuiInputEvent e;
    e.Type = ImGuiInputEventType_MouseWheel;
    e.Source = ImGuiInputSource_Mouse;
    e.EventId = g.InputEventsNextEventId++;
    e.MouseWheel.WheelX = wheel_x;
    e.MouseWheel.WheelY = wheel_y;
    e.MouseWheel.MouseSource = g.InputEventsNextMouseSource;
    g.InputEventsQueue.push_back(e);
}

// This is not a real event, the data is latched in order to be stored in actual Mouse events.
// This is so that duplicate events (e.g. Windows sending extraneous WM_MOUSEMOVE) gets filtered and are not leading to actual source changes.
void ImGuiIO::AddMouseSourceEvent(ImGuiMouseSource source)
{
    IM_ASSERT(Ctx != NULL);
    ImGuiContext& g = *Ctx;
    g.InputEventsNextMouseSource = source;
}

void ImGuiIO::AddMouseViewportEvent(ImGuiID viewport_id)
{
    IM_ASSERT(Ctx != NULL);
    ImGuiContext& g = *Ctx;
    //IM_ASSERT(g.IO.BackendFlags & ImGuiBackendFlags_HasMouseHoveredViewport);
    if (!AppAcceptingEvents)
        return;

    // Filter duplicate
    const ImGuiInputEvent* latest_event = FindLatestInputEvent(&g, ImGuiInputEventType_MouseViewport);
    const ImGuiID latest_viewport_id = latest_event ? latest_event->MouseViewport.HoveredViewportID : g.IO.MouseHoveredViewport;
    if (latest_viewport_id == viewport_id)
        return;

    ImGuiInputEvent e;
    e.Type = ImGuiInputEventType_MouseViewport;
    e.Source = ImGuiInputSource_Mouse;
    e.MouseViewport.HoveredViewportID = viewport_id;
    g.InputEventsQueue.push_back(e);
}

void ImGuiIO::AddFocusEvent(bool focused)
{
    IM_ASSERT(Ctx != NULL);
    ImGuiContext& g = *Ctx;

    // Filter duplicate
    const ImGuiInputEvent* latest_event = FindLatestInputEvent(&g, ImGuiInputEventType_Focus);
    const bool latest_focused = latest_event ? latest_event->AppFocused.Focused : !g.IO.AppFocusLost;
    if (latest_focused == focused || (ConfigDebugIgnoreFocusLoss && !focused))
        return;

    ImGuiInputEvent e;
    e.Type = ImGuiInputEventType_Focus;
    e.EventId = g.InputEventsNextEventId++;
    e.AppFocused.Focused = focused;
    g.InputEventsQueue.push_back(e);
}

//-----------------------------------------------------------------------------
// [SECTION] MISC HELPERS/UTILITIES (Geometry functions)
//-----------------------------------------------------------------------------

ImVec2 ImBezierCubicClosestPoint(const ImVec2& p1, const ImVec2& p2, const ImVec2& p3, const ImVec2& p4, const ImVec2& p, int num_segments)
{
    IM_ASSERT(num_segments > 0); // Use ImBezierCubicClosestPointCasteljau()
    ImVec2 p_last = p1;
    ImVec2 p_closest;
    float p_closest_dist2 = FLT_MAX;
    float t_step = 1.0f / (float)num_segments;
    for (int i_step = 1; i_step <= num_segments; i_step++)
    {
        ImVec2 p_current = ImBezierCubicCalc(p1, p2, p3, p4, t_step * i_step);
        ImVec2 p_line = ImLineClosestPoint(p_last, p_current, p);
        float dist2 = ImLengthSqr(p - p_line);
        if (dist2 < p_closest_dist2)
        {
            p_closest = p_line;
            p_closest_dist2 = dist2;
        }
        p_last = p_current;
    }
    return p_closest;
}

// Closely mimics PathBezierToCasteljau() in imgui_draw.cpp
static void ImBezierCubicClosestPointCasteljauStep(const ImVec2& p, ImVec2& p_closest, ImVec2& p_last, float& p_closest_dist2, float x1, float y1, float x2, float y2, float x3, float y3, float x4, float y4, float tess_tol, int level)
{
    float dx = x4 - x1;
    float dy = y4 - y1;
    float d2 = ((x2 - x4) * dy - (y2 - y4) * dx);
    float d3 = ((x3 - x4) * dy - (y3 - y4) * dx);
    d2 = (d2 >= 0) ? d2 : -d2;
    d3 = (d3 >= 0) ? d3 : -d3;
    if ((d2 + d3) * (d2 + d3) < tess_tol * (dx * dx + dy * dy))
    {
        ImVec2 p_current(x4, y4);
        ImVec2 p_line = ImLineClosestPoint(p_last, p_current, p);
        float dist2 = ImLengthSqr(p - p_line);
        if (dist2 < p_closest_dist2)
        {
            p_closest = p_line;
            p_closest_dist2 = dist2;
        }
        p_last = p_current;
    }
    else if (level < 10)
    {
        float x12 = (x1 + x2)*0.5f,       y12 = (y1 + y2)*0.5f;
        float x23 = (x2 + x3)*0.5f,       y23 = (y2 + y3)*0.5f;
        float x34 = (x3 + x4)*0.5f,       y34 = (y3 + y4)*0.5f;
        float x123 = (x12 + x23)*0.5f,    y123 = (y12 + y23)*0.5f;
        float x234 = (x23 + x34)*0.5f,    y234 = (y23 + y34)*0.5f;
        float x1234 = (x123 + x234)*0.5f, y1234 = (y123 + y234)*0.5f;
        ImBezierCubicClosestPointCasteljauStep(p, p_closest, p_last, p_closest_dist2, x1, y1, x12, y12, x123, y123, x1234, y1234, tess_tol, level + 1);
        ImBezierCubicClosestPointCasteljauStep(p, p_closest, p_last, p_closest_dist2, x1234, y1234, x234, y234, x34, y34, x4, y4, tess_tol, level + 1);
    }
}

// tess_tol is generally the same value you would find in ImGui::GetStyle().CurveTessellationTol
// Because those ImXXX functions are lower-level than ImGui:: we cannot access this value automatically.
ImVec2 ImBezierCubicClosestPointCasteljau(const ImVec2& p1, const ImVec2& p2, const ImVec2& p3, const ImVec2& p4, const ImVec2& p, float tess_tol)
{
    IM_ASSERT(tess_tol > 0.0f);
    ImVec2 p_last = p1;
    ImVec2 p_closest;
    float p_closest_dist2 = FLT_MAX;
    ImBezierCubicClosestPointCasteljauStep(p, p_closest, p_last, p_closest_dist2, p1.x, p1.y, p2.x, p2.y, p3.x, p3.y, p4.x, p4.y, tess_tol, 0);
    return p_closest;
}

ImVec2 ImLineClosestPoint(const ImVec2& a, const ImVec2& b, const ImVec2& p)
{
    ImVec2 ap = p - a;
    ImVec2 ab_dir = b - a;
    float dot = ap.x * ab_dir.x + ap.y * ab_dir.y;
    if (dot < 0.0f)
        return a;
    float ab_len_sqr = ab_dir.x * ab_dir.x + ab_dir.y * ab_dir.y;
    if (dot > ab_len_sqr)
        return b;
    return a + ab_dir * dot / ab_len_sqr;
}

bool ImTriangleContainsPoint(const ImVec2& a, const ImVec2& b, const ImVec2& c, const ImVec2& p)
{
    bool b1 = ((p.x - b.x) * (a.y - b.y) - (p.y - b.y) * (a.x - b.x)) < 0.0f;
    bool b2 = ((p.x - c.x) * (b.y - c.y) - (p.y - c.y) * (b.x - c.x)) < 0.0f;
    bool b3 = ((p.x - a.x) * (c.y - a.y) - (p.y - a.y) * (c.x - a.x)) < 0.0f;
    return ((b1 == b2) && (b2 == b3));
}

void ImTriangleBarycentricCoords(const ImVec2& a, const ImVec2& b, const ImVec2& c, const ImVec2& p, float& out_u, float& out_v, float& out_w)
{
    ImVec2 v0 = b - a;
    ImVec2 v1 = c - a;
    ImVec2 v2 = p - a;
    const float denom = v0.x * v1.y - v1.x * v0.y;
    out_v = (v2.x * v1.y - v1.x * v2.y) / denom;
    out_w = (v0.x * v2.y - v2.x * v0.y) / denom;
    out_u = 1.0f - out_v - out_w;
}

ImVec2 ImTriangleClosestPoint(const ImVec2& a, const ImVec2& b, const ImVec2& c, const ImVec2& p)
{
    ImVec2 proj_ab = ImLineClosestPoint(a, b, p);
    ImVec2 proj_bc = ImLineClosestPoint(b, c, p);
    ImVec2 proj_ca = ImLineClosestPoint(c, a, p);
    float dist2_ab = ImLengthSqr(p - proj_ab);
    float dist2_bc = ImLengthSqr(p - proj_bc);
    float dist2_ca = ImLengthSqr(p - proj_ca);
    float m = ImMin(dist2_ab, ImMin(dist2_bc, dist2_ca));
    if (m == dist2_ab)
        return proj_ab;
    if (m == dist2_bc)
        return proj_bc;
    return proj_ca;
}

//-----------------------------------------------------------------------------
// [SECTION] MISC HELPERS/UTILITIES (String, Format, Hash functions)
//-----------------------------------------------------------------------------

// Consider using _stricmp/_strnicmp under Windows or strcasecmp/strncasecmp. We don't actually use either ImStricmp/ImStrnicmp in the codebase any more.
int ImStricmp(const char* str1, const char* str2)
{
    int d;
    while ((d = ImToUpper(*str2) - ImToUpper(*str1)) == 0 && *str1) { str1++; str2++; }
    return d;
}

int ImStrnicmp(const char* str1, const char* str2, size_t count)
{
    int d = 0;
    while (count > 0 && (d = ImToUpper(*str2) - ImToUpper(*str1)) == 0 && *str1) { str1++; str2++; count--; }
    return d;
}

void ImStrncpy(char* dst, const char* src, size_t count)
{
    if (count < 1)
        return;
    if (count > 1)
        strncpy(dst, src, count - 1);
    dst[count - 1] = 0;
}

char* ImStrdup(const char* str)
{
    size_t len = strlen(str);
    void* buf = IM_ALLOC(len + 1);
    return (char*)memcpy(buf, (const void*)str, len + 1);
}

char* ImStrdupcpy(char* dst, size_t* p_dst_size, const char* src)
{
    size_t dst_buf_size = p_dst_size ? *p_dst_size : strlen(dst) + 1;
    size_t src_size = strlen(src) + 1;
    if (dst_buf_size < src_size)
    {
        IM_FREE(dst);
        dst = (char*)IM_ALLOC(src_size);
        if (p_dst_size)
            *p_dst_size = src_size;
    }
    return (char*)memcpy(dst, (const void*)src, src_size);
}

const char* ImStrchrRange(const char* str, const char* str_end, char c)
{
    const char* p = (const char*)memchr(str, (int)c, str_end - str);
    return p;
}

int ImStrlenW(const ImWchar* str)
{
    //return (int)wcslen((const wchar_t*)str);  // FIXME-OPT: Could use this when wchar_t are 16-bit
    int n = 0;
    while (*str++) n++;
    return n;
}

// Find end-of-line. Return pointer will point to either first \n, either str_end.
const char* ImStreolRange(const char* str, const char* str_end)
{
    const char* p = (const char*)memchr(str, '\n', str_end - str);
    return p ? p : str_end;
}

const ImWchar* ImStrbolW(const ImWchar* buf_mid_line, const ImWchar* buf_begin) // find beginning-of-line
{
    while (buf_mid_line > buf_begin && buf_mid_line[-1] != '\n')
        buf_mid_line--;
    return buf_mid_line;
}

const char* ImStristr(const char* haystack, const char* haystack_end, const char* needle, const char* needle_end)
{
    if (!needle_end)
        needle_end = needle + strlen(needle);

    const char un0 = (char)ImToUpper(*needle);
    while ((!haystack_end && *haystack) || (haystack_end && haystack < haystack_end))
    {
        if (ImToUpper(*haystack) == un0)
        {
            const char* b = needle + 1;
            for (const char* a = haystack + 1; b < needle_end; a++, b++)
                if (ImToUpper(*a) != ImToUpper(*b))
                    break;
            if (b == needle_end)
                return haystack;
        }
        haystack++;
    }
    return NULL;
}

// Trim str by offsetting contents when there's leading data + writing a \0 at the trailing position. We use this in situation where the cost is negligible.
void ImStrTrimBlanks(char* buf)
{
    char* p = buf;
    while (p[0] == ' ' || p[0] == '\t')     // Leading blanks
        p++;
    char* p_start = p;
    while (*p != 0)                         // Find end of string
        p++;
    while (p > p_start && (p[-1] == ' ' || p[-1] == '\t'))  // Trailing blanks
        p--;
    if (p_start != buf)                     // Copy memory if we had leading blanks
        memmove(buf, p_start, p - p_start);
    buf[p - p_start] = 0;                   // Zero terminate
}

const char* ImStrSkipBlank(const char* str)
{
    while (str[0] == ' ' || str[0] == '\t')
        str++;
    return str;
}

// A) MSVC version appears to return -1 on overflow, whereas glibc appears to return total count (which may be >= buf_size).
// Ideally we would test for only one of those limits at runtime depending on the behavior the vsnprintf(), but trying to deduct it at compile time sounds like a pandora can of worm.
// B) When buf==NULL vsnprintf() will return the output size.
#ifndef IMGUI_DISABLE_DEFAULT_FORMAT_FUNCTIONS

// We support stb_sprintf which is much faster (see: https://github.com/nothings/stb/blob/master/stb_sprintf.h)
// You may set IMGUI_USE_STB_SPRINTF to use our default wrapper, or set IMGUI_DISABLE_DEFAULT_FORMAT_FUNCTIONS
// and setup the wrapper yourself. (FIXME-OPT: Some of our high-level operations such as ImGuiTextBuffer::appendfv() are
// designed using two-passes worst case, which probably could be improved using the stbsp_vsprintfcb() function.)
#ifdef IMGUI_USE_STB_SPRINTF
#ifndef IMGUI_DISABLE_STB_SPRINTF_IMPLEMENTATION
#define STB_SPRINTF_IMPLEMENTATION
#endif
#ifdef IMGUI_STB_SPRINTF_FILENAME
#include IMGUI_STB_SPRINTF_FILENAME
#else
#include "stb_sprintf.h"
#endif
#endif // #ifdef IMGUI_USE_STB_SPRINTF

#if defined(_MSC_VER) && !defined(vsnprintf)
#define vsnprintf _vsnprintf
#endif

int ImFormatString(char* buf, size_t buf_size, const char* fmt, ...)
{
    va_list args;
    va_start(args, fmt);
#ifdef IMGUI_USE_STB_SPRINTF
    int w = stbsp_vsnprintf(buf, (int)buf_size, fmt, args);
#else
    int w = vsnprintf(buf, buf_size, fmt, args);
#endif
    va_end(args);
    if (buf == NULL)
        return w;
    if (w == -1 || w >= (int)buf_size)
        w = (int)buf_size - 1;
    buf[w] = 0;
    return w;
}

int ImFormatStringV(char* buf, size_t buf_size, const char* fmt, va_list args)
{
#ifdef IMGUI_USE_STB_SPRINTF
    int w = stbsp_vsnprintf(buf, (int)buf_size, fmt, args);
#else
    int w = vsnprintf(buf, buf_size, fmt, args);
#endif
    if (buf == NULL)
        return w;
    if (w == -1 || w >= (int)buf_size)
        w = (int)buf_size - 1;
    buf[w] = 0;
    return w;
}
#endif // #ifdef IMGUI_DISABLE_DEFAULT_FORMAT_FUNCTIONS

void ImFormatStringToTempBuffer(const char** out_buf, const char** out_buf_end, const char* fmt, ...)
{
    va_list args;
    va_start(args, fmt);
    ImFormatStringToTempBufferV(out_buf, out_buf_end, fmt, args);
    va_end(args);
}

void ImFormatStringToTempBufferV(const char** out_buf, const char** out_buf_end, const char* fmt, va_list args)
{
    ImGuiContext& g = *GImGui;
    if (fmt[0] == '%' && fmt[1] == 's' && fmt[2] == 0)
    {
        const char* buf = va_arg(args, const char*); // Skip formatting when using "%s"
        *out_buf = buf;
        if (out_buf_end) { *out_buf_end = buf + strlen(buf); }
    }
    else if (fmt[0] == '%' && fmt[1] == '.' && fmt[2] == '*' && fmt[3] == 's' && fmt[4] == 0)
    {
        int buf_len = va_arg(args, int); // Skip formatting when using "%.*s"
        const char* buf = va_arg(args, const char*);
        *out_buf = buf;
        *out_buf_end = buf + buf_len; // Disallow not passing 'out_buf_end' here. User is expected to use it.
    }
    else
    {
        int buf_len = ImFormatStringV(g.TempBuffer.Data, g.TempBuffer.Size, fmt, args);
        *out_buf = g.TempBuffer.Data;
        if (out_buf_end) { *out_buf_end = g.TempBuffer.Data + buf_len; }
    }
}

// CRC32 needs a 1KB lookup table (not cache friendly)
// Although the code to generate the table is simple and shorter than the table itself, using a const table allows us to easily:
// - avoid an unnecessary branch/memory tap, - keep the ImHashXXX functions usable by static constructors, - make it thread-safe.
static const ImU32 GCrc32LookupTable[256] =
{
    0x00000000,0x77073096,0xEE0E612C,0x990951BA,0x076DC419,0x706AF48F,0xE963A535,0x9E6495A3,0x0EDB8832,0x79DCB8A4,0xE0D5E91E,0x97D2D988,0x09B64C2B,0x7EB17CBD,0xE7B82D07,0x90BF1D91,
    0x1DB71064,0x6AB020F2,0xF3B97148,0x84BE41DE,0x1ADAD47D,0x6DDDE4EB,0xF4D4B551,0x83D385C7,0x136C9856,0x646BA8C0,0xFD62F97A,0x8A65C9EC,0x14015C4F,0x63066CD9,0xFA0F3D63,0x8D080DF5,
    0x3B6E20C8,0x4C69105E,0xD56041E4,0xA2677172,0x3C03E4D1,0x4B04D447,0xD20D85FD,0xA50AB56B,0x35B5A8FA,0x42B2986C,0xDBBBC9D6,0xACBCF940,0x32D86CE3,0x45DF5C75,0xDCD60DCF,0xABD13D59,
    0x26D930AC,0x51DE003A,0xC8D75180,0xBFD06116,0x21B4F4B5,0x56B3C423,0xCFBA9599,0xB8BDA50F,0x2802B89E,0x5F058808,0xC60CD9B2,0xB10BE924,0x2F6F7C87,0x58684C11,0xC1611DAB,0xB6662D3D,
    0x76DC4190,0x01DB7106,0x98D220BC,0xEFD5102A,0x71B18589,0x06B6B51F,0x9FBFE4A5,0xE8B8D433,0x7807C9A2,0x0F00F934,0x9609A88E,0xE10E9818,0x7F6A0DBB,0x086D3D2D,0x91646C97,0xE6635C01,
    0x6B6B51F4,0x1C6C6162,0x856530D8,0xF262004E,0x6C0695ED,0x1B01A57B,0x8208F4C1,0xF50FC457,0x65B0D9C6,0x12B7E950,0x8BBEB8EA,0xFCB9887C,0x62DD1DDF,0x15DA2D49,0x8CD37CF3,0xFBD44C65,
    0x4DB26158,0x3AB551CE,0xA3BC0074,0xD4BB30E2,0x4ADFA541,0x3DD895D7,0xA4D1C46D,0xD3D6F4FB,0x4369E96A,0x346ED9FC,0xAD678846,0xDA60B8D0,0x44042D73,0x33031DE5,0xAA0A4C5F,0xDD0D7CC9,
    0x5005713C,0x270241AA,0xBE0B1010,0xC90C2086,0x5768B525,0x206F85B3,0xB966D409,0xCE61E49F,0x5EDEF90E,0x29D9C998,0xB0D09822,0xC7D7A8B4,0x59B33D17,0x2EB40D81,0xB7BD5C3B,0xC0BA6CAD,
    0xEDB88320,0x9ABFB3B6,0x03B6E20C,0x74B1D29A,0xEAD54739,0x9DD277AF,0x04DB2615,0x73DC1683,0xE3630B12,0x94643B84,0x0D6D6A3E,0x7A6A5AA8,0xE40ECF0B,0x9309FF9D,0x0A00AE27,0x7D079EB1,
    0xF00F9344,0x8708A3D2,0x1E01F268,0x6906C2FE,0xF762575D,0x806567CB,0x196C3671,0x6E6B06E7,0xFED41B76,0x89D32BE0,0x10DA7A5A,0x67DD4ACC,0xF9B9DF6F,0x8EBEEFF9,0x17B7BE43,0x60B08ED5,
    0xD6D6A3E8,0xA1D1937E,0x38D8C2C4,0x4FDFF252,0xD1BB67F1,0xA6BC5767,0x3FB506DD,0x48B2364B,0xD80D2BDA,0xAF0A1B4C,0x36034AF6,0x41047A60,0xDF60EFC3,0xA867DF55,0x316E8EEF,0x4669BE79,
    0xCB61B38C,0xBC66831A,0x256FD2A0,0x5268E236,0xCC0C7795,0xBB0B4703,0x220216B9,0x5505262F,0xC5BA3BBE,0xB2BD0B28,0x2BB45A92,0x5CB36A04,0xC2D7FFA7,0xB5D0CF31,0x2CD99E8B,0x5BDEAE1D,
    0x9B64C2B0,0xEC63F226,0x756AA39C,0x026D930A,0x9C0906A9,0xEB0E363F,0x72076785,0x05005713,0x95BF4A82,0xE2B87A14,0x7BB12BAE,0x0CB61B38,0x92D28E9B,0xE5D5BE0D,0x7CDCEFB7,0x0BDBDF21,
    0x86D3D2D4,0xF1D4E242,0x68DDB3F8,0x1FDA836E,0x81BE16CD,0xF6B9265B,0x6FB077E1,0x18B74777,0x88085AE6,0xFF0F6A70,0x66063BCA,0x11010B5C,0x8F659EFF,0xF862AE69,0x616BFFD3,0x166CCF45,
    0xA00AE278,0xD70DD2EE,0x4E048354,0x3903B3C2,0xA7672661,0xD06016F7,0x4969474D,0x3E6E77DB,0xAED16A4A,0xD9D65ADC,0x40DF0B66,0x37D83BF0,0xA9BCAE53,0xDEBB9EC5,0x47B2CF7F,0x30B5FFE9,
    0xBDBDF21C,0xCABAC28A,0x53B39330,0x24B4A3A6,0xBAD03605,0xCDD70693,0x54DE5729,0x23D967BF,0xB3667A2E,0xC4614AB8,0x5D681B02,0x2A6F2B94,0xB40BBE37,0xC30C8EA1,0x5A05DF1B,0x2D02EF8D,
};

// Known size hash
// It is ok to call ImHashData on a string with known length but the ### operator won't be supported.
// FIXME-OPT: Replace with e.g. FNV1a hash? CRC32 pretty much randomly access 1KB. Need to do proper measurements.
ImGuiID ImHashData(const void* data_p, size_t data_size, ImGuiID seed)
{
    ImU32 crc = ~seed;
    const unsigned char* data = (const unsigned char*)data_p;
    const ImU32* crc32_lut = GCrc32LookupTable;
    while (data_size-- != 0)
        crc = (crc >> 8) ^ crc32_lut[(crc & 0xFF) ^ *data++];
    return ~crc;
}

// Zero-terminated string hash, with support for ### to reset back to seed value
// We support a syntax of "label###id" where only "###id" is included in the hash, and only "label" gets displayed.
// Because this syntax is rarely used we are optimizing for the common case.
// - If we reach ### in the string we discard the hash so far and reset to the seed.
// - We don't do 'current += 2; continue;' after handling ### to keep the code smaller/faster (measured ~10% diff in Debug build)
// FIXME-OPT: Replace with e.g. FNV1a hash? CRC32 pretty much randomly access 1KB. Need to do proper measurements.
ImGuiID ImHashStr(const char* data_p, size_t data_size, ImGuiID seed)
{
    seed = ~seed;
    ImU32 crc = seed;
    const unsigned char* data = (const unsigned char*)data_p;
    const ImU32* crc32_lut = GCrc32LookupTable;
    if (data_size != 0)
    {
        while (data_size-- != 0)
        {
            unsigned char c = *data++;
            if (c == '#' && data_size >= 2 && data[0] == '#' && data[1] == '#')
                crc = seed;
            crc = (crc >> 8) ^ crc32_lut[(crc & 0xFF) ^ c];
        }
    }
    else
    {
        while (unsigned char c = *data++)
        {
            if (c == '#' && data[0] == '#' && data[1] == '#')
                crc = seed;
            crc = (crc >> 8) ^ crc32_lut[(crc & 0xFF) ^ c];
        }
    }
    return ~crc;
}

//-----------------------------------------------------------------------------
// [SECTION] MISC HELPERS/UTILITIES (File functions)
//-----------------------------------------------------------------------------

// Default file functions
#ifndef IMGUI_DISABLE_DEFAULT_FILE_FUNCTIONS

ImFileHandle ImFileOpen(const char* filename, const char* mode)
{
#if defined(_WIN32) && !defined(IMGUI_DISABLE_WIN32_FUNCTIONS) && !defined(__CYGWIN__) && !defined(__GNUC__)
    // We need a fopen() wrapper because MSVC/Windows fopen doesn't handle UTF-8 filenames.
    // Previously we used ImTextCountCharsFromUtf8/ImTextStrFromUtf8 here but we now need to support ImWchar16 and ImWchar32!
    const int filename_wsize = ::MultiByteToWideChar(CP_UTF8, 0, filename, -1, NULL, 0);
    const int mode_wsize = ::MultiByteToWideChar(CP_UTF8, 0, mode, -1, NULL, 0);
    ImGuiContext& g = *GImGui;
    g.TempBuffer.reserve((filename_wsize + mode_wsize) * sizeof(wchar_t));
    wchar_t* buf = (wchar_t*)(void*)g.TempBuffer.Data;
    ::MultiByteToWideChar(CP_UTF8, 0, filename, -1, (wchar_t*)&buf[0], filename_wsize);
    ::MultiByteToWideChar(CP_UTF8, 0, mode, -1, (wchar_t*)&buf[filename_wsize], mode_wsize);
    return ::_wfopen((const wchar_t*)&buf[0], (const wchar_t*)&buf[filename_wsize]);
#else
    return fopen(filename, mode);
#endif
}

// We should in theory be using fseeko()/ftello() with off_t and _fseeki64()/_ftelli64() with __int64, waiting for the PR that does that in a very portable pre-C++11 zero-warnings way.
bool    ImFileClose(ImFileHandle f)     { return fclose(f) == 0; }
ImU64   ImFileGetSize(ImFileHandle f)   { long off = 0, sz = 0; return ((off = ftell(f)) != -1 && !fseek(f, 0, SEEK_END) && (sz = ftell(f)) != -1 && !fseek(f, off, SEEK_SET)) ? (ImU64)sz : (ImU64)-1; }
ImU64   ImFileRead(void* data, ImU64 sz, ImU64 count, ImFileHandle f)           { return fread(data, (size_t)sz, (size_t)count, f); }
ImU64   ImFileWrite(const void* data, ImU64 sz, ImU64 count, ImFileHandle f)    { return fwrite(data, (size_t)sz, (size_t)count, f); }
#endif // #ifndef IMGUI_DISABLE_DEFAULT_FILE_FUNCTIONS

// Helper: Load file content into memory
// Memory allocated with IM_ALLOC(), must be freed by user using IM_FREE() == ImGui::MemFree()
// This can't really be used with "rt" because fseek size won't match read size.
void*   ImFileLoadToMemory(const char* filename, const char* mode, size_t* out_file_size, int padding_bytes)
{
    IM_ASSERT(filename && mode);
    if (out_file_size)
        *out_file_size = 0;

    ImFileHandle f;
    if ((f = ImFileOpen(filename, mode)) == NULL)
        return NULL;

    size_t file_size = (size_t)ImFileGetSize(f);
    if (file_size == (size_t)-1)
    {
        ImFileClose(f);
        return NULL;
    }

    void* file_data = IM_ALLOC(file_size + padding_bytes);
    if (file_data == NULL)
    {
        ImFileClose(f);
        return NULL;
    }
    if (ImFileRead(file_data, 1, file_size, f) != file_size)
    {
        ImFileClose(f);
        IM_FREE(file_data);
        return NULL;
    }
    if (padding_bytes > 0)
        memset((void*)(((char*)file_data) + file_size), 0, (size_t)padding_bytes);

    ImFileClose(f);
    if (out_file_size)
        *out_file_size = file_size;

    return file_data;
}

//-----------------------------------------------------------------------------
// [SECTION] MISC HELPERS/UTILITIES (ImText* functions)
//-----------------------------------------------------------------------------

IM_MSVC_RUNTIME_CHECKS_OFF

// Convert UTF-8 to 32-bit character, process single character input.
// A nearly-branchless UTF-8 decoder, based on work of Christopher Wellons (https://github.com/skeeto/branchless-utf8).
// We handle UTF-8 decoding error by skipping forward.
int ImTextCharFromUtf8(unsigned int* out_char, const char* in_text, const char* in_text_end)
{
    static const char lengths[32] = { 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 2, 2, 3, 3, 4, 0 };
    static const int masks[]  = { 0x00, 0x7f, 0x1f, 0x0f, 0x07 };
    static const uint32_t mins[] = { 0x400000, 0, 0x80, 0x800, 0x10000 };
    static const int shiftc[] = { 0, 18, 12, 6, 0 };
    static const int shifte[] = { 0, 6, 4, 2, 0 };
    int len = lengths[*(const unsigned char*)in_text >> 3];
    int wanted = len + (len ? 0 : 1);

    if (in_text_end == NULL)
        in_text_end = in_text + wanted; // Max length, nulls will be taken into account.

    // Copy at most 'len' bytes, stop copying at 0 or past in_text_end. Branch predictor does a good job here,
    // so it is fast even with excessive branching.
    unsigned char s[4];
    s[0] = in_text + 0 < in_text_end ? in_text[0] : 0;
    s[1] = in_text + 1 < in_text_end ? in_text[1] : 0;
    s[2] = in_text + 2 < in_text_end ? in_text[2] : 0;
    s[3] = in_text + 3 < in_text_end ? in_text[3] : 0;

    // Assume a four-byte character and load four bytes. Unused bits are shifted out.
    *out_char  = (uint32_t)(s[0] & masks[len]) << 18;
    *out_char |= (uint32_t)(s[1] & 0x3f) << 12;
    *out_char |= (uint32_t)(s[2] & 0x3f) <<  6;
    *out_char |= (uint32_t)(s[3] & 0x3f) <<  0;
    *out_char >>= shiftc[len];

    // Accumulate the various error conditions.
    int e = 0;
    e  = (*out_char < mins[len]) << 6; // non-canonical encoding
    e |= ((*out_char >> 11) == 0x1b) << 7;  // surrogate half?
    e |= (*out_char > IM_UNICODE_CODEPOINT_MAX) << 8;  // out of range?
    e |= (s[1] & 0xc0) >> 2;
    e |= (s[2] & 0xc0) >> 4;
    e |= (s[3]       ) >> 6;
    e ^= 0x2a; // top two bits of each tail byte correct?
    e >>= shifte[len];

    if (e)
    {
        // No bytes are consumed when *in_text == 0 || in_text == in_text_end.
        // One byte is consumed in case of invalid first byte of in_text.
        // All available bytes (at most `len` bytes) are consumed on incomplete/invalid second to last bytes.
        // Invalid or incomplete input may consume less bytes than wanted, therefore every byte has to be inspected in s.
        wanted = ImMin(wanted, !!s[0] + !!s[1] + !!s[2] + !!s[3]);
        *out_char = IM_UNICODE_CODEPOINT_INVALID;
    }

    return wanted;
}

int ImTextStrFromUtf8(ImWchar* buf, int buf_size, const char* in_text, const char* in_text_end, const char** in_text_remaining)
{
    ImWchar* buf_out = buf;
    ImWchar* buf_end = buf + buf_size;
    while (buf_out < buf_end - 1 && (!in_text_end || in_text < in_text_end) && *in_text)
    {
        unsigned int c;
        in_text += ImTextCharFromUtf8(&c, in_text, in_text_end);
        *buf_out++ = (ImWchar)c;
    }
    *buf_out = 0;
    if (in_text_remaining)
        *in_text_remaining = in_text;
    return (int)(buf_out - buf);
}

int ImTextCountCharsFromUtf8(const char* in_text, const char* in_text_end)
{
    int char_count = 0;
    while ((!in_text_end || in_text < in_text_end) && *in_text)
    {
        unsigned int c;
        in_text += ImTextCharFromUtf8(&c, in_text, in_text_end);
        char_count++;
    }
    return char_count;
}

// Based on stb_to_utf8() from github.com/nothings/stb/
static inline int ImTextCharToUtf8_inline(char* buf, int buf_size, unsigned int c)
{
    if (c < 0x80)
    {
        buf[0] = (char)c;
        return 1;
    }
    if (c < 0x800)
    {
        if (buf_size < 2) return 0;
        buf[0] = (char)(0xc0 + (c >> 6));
        buf[1] = (char)(0x80 + (c & 0x3f));
        return 2;
    }
    if (c < 0x10000)
    {
        if (buf_size < 3) return 0;
        buf[0] = (char)(0xe0 + (c >> 12));
        buf[1] = (char)(0x80 + ((c >> 6) & 0x3f));
        buf[2] = (char)(0x80 + ((c ) & 0x3f));
        return 3;
    }
    if (c <= 0x10FFFF)
    {
        if (buf_size < 4) return 0;
        buf[0] = (char)(0xf0 + (c >> 18));
        buf[1] = (char)(0x80 + ((c >> 12) & 0x3f));
        buf[2] = (char)(0x80 + ((c >> 6) & 0x3f));
        buf[3] = (char)(0x80 + ((c ) & 0x3f));
        return 4;
    }
    // Invalid code point, the max unicode is 0x10FFFF
    return 0;
}

const char* ImTextCharToUtf8(char out_buf[5], unsigned int c)
{
    int count = ImTextCharToUtf8_inline(out_buf, 5, c);
    out_buf[count] = 0;
    return out_buf;
}

// Not optimal but we very rarely use this function.
int ImTextCountUtf8BytesFromChar(const char* in_text, const char* in_text_end)
{
    unsigned int unused = 0;
    return ImTextCharFromUtf8(&unused, in_text, in_text_end);
}

static inline int ImTextCountUtf8BytesFromChar(unsigned int c)
{
    if (c < 0x80) return 1;
    if (c < 0x800) return 2;
    if (c < 0x10000) return 3;
    if (c <= 0x10FFFF) return 4;
    return 3;
}

int ImTextStrToUtf8(char* out_buf, int out_buf_size, const ImWchar* in_text, const ImWchar* in_text_end)
{
    char* buf_p = out_buf;
    const char* buf_end = out_buf + out_buf_size;
    while (buf_p < buf_end - 1 && (!in_text_end || in_text < in_text_end) && *in_text)
    {
        unsigned int c = (unsigned int)(*in_text++);
        if (c < 0x80)
            *buf_p++ = (char)c;
        else
            buf_p += ImTextCharToUtf8_inline(buf_p, (int)(buf_end - buf_p - 1), c);
    }
    *buf_p = 0;
    return (int)(buf_p - out_buf);
}

int ImTextCountUtf8BytesFromStr(const ImWchar* in_text, const ImWchar* in_text_end)
{
    int bytes_count = 0;
    while ((!in_text_end || in_text < in_text_end) && *in_text)
    {
        unsigned int c = (unsigned int)(*in_text++);
        if (c < 0x80)
            bytes_count++;
        else
            bytes_count += ImTextCountUtf8BytesFromChar(c);
    }
    return bytes_count;
}

const char* ImTextFindPreviousUtf8Codepoint(const char* in_text_start, const char* in_text_curr)
{
    while (in_text_curr > in_text_start)
    {
        in_text_curr--;
        if ((*in_text_curr & 0xC0) != 0x80)
            return in_text_curr;
    }
    return in_text_start;
}

IM_MSVC_RUNTIME_CHECKS_RESTORE

//-----------------------------------------------------------------------------
// [SECTION] MISC HELPERS/UTILITIES (Color functions)
// Note: The Convert functions are early design which are not consistent with other API.
//-----------------------------------------------------------------------------

IMGUI_API ImU32 ImAlphaBlendColors(ImU32 col_a, ImU32 col_b)
{
    float t = ((col_b >> IM_COL32_A_SHIFT) & 0xFF) / 255.f;
    int r = ImLerp((int)(col_a >> IM_COL32_R_SHIFT) & 0xFF, (int)(col_b >> IM_COL32_R_SHIFT) & 0xFF, t);
    int g = ImLerp((int)(col_a >> IM_COL32_G_SHIFT) & 0xFF, (int)(col_b >> IM_COL32_G_SHIFT) & 0xFF, t);
    int b = ImLerp((int)(col_a >> IM_COL32_B_SHIFT) & 0xFF, (int)(col_b >> IM_COL32_B_SHIFT) & 0xFF, t);
    return IM_COL32(r, g, b, 0xFF);
}

ImVec4 ImGui::ColorConvertU32ToFloat4(ImU32 in)
{
    float s = 1.0f / 255.0f;
    return ImVec4(
        ((in >> IM_COL32_R_SHIFT) & 0xFF) * s,
        ((in >> IM_COL32_G_SHIFT) & 0xFF) * s,
        ((in >> IM_COL32_B_SHIFT) & 0xFF) * s,
        ((in >> IM_COL32_A_SHIFT) & 0xFF) * s);
}

ImU32 ImGui::ColorConvertFloat4ToU32(const ImVec4& in)
{
    ImU32 out;
    out  = ((ImU32)IM_F32_TO_INT8_SAT(in.x)) << IM_COL32_R_SHIFT;
    out |= ((ImU32)IM_F32_TO_INT8_SAT(in.y)) << IM_COL32_G_SHIFT;
    out |= ((ImU32)IM_F32_TO_INT8_SAT(in.z)) << IM_COL32_B_SHIFT;
    out |= ((ImU32)IM_F32_TO_INT8_SAT(in.w)) << IM_COL32_A_SHIFT;
    return out;
}

// Convert rgb floats ([0-1],[0-1],[0-1]) to hsv floats ([0-1],[0-1],[0-1]), from Foley & van Dam p592
// Optimized http://lolengine.net/blog/2013/01/13/fast-rgb-to-hsv
void ImGui::ColorConvertRGBtoHSV(float r, float g, float b, float& out_h, float& out_s, float& out_v)
{
    float K = 0.f;
    if (g < b)
    {
        ImSwap(g, b);
        K = -1.f;
    }
    if (r < g)
    {
        ImSwap(r, g);
        K = -2.f / 6.f - K;
    }

    const float chroma = r - (g < b ? g : b);
    out_h = ImFabs(K + (g - b) / (6.f * chroma + 1e-20f));
    out_s = chroma / (r + 1e-20f);
    out_v = r;
}

// Convert hsv floats ([0-1],[0-1],[0-1]) to rgb floats ([0-1],[0-1],[0-1]), from Foley & van Dam p593
// also http://en.wikipedia.org/wiki/HSL_and_HSV
void ImGui::ColorConvertHSVtoRGB(float h, float s, float v, float& out_r, float& out_g, float& out_b)
{
    if (s == 0.0f)
    {
        // gray
        out_r = out_g = out_b = v;
        return;
    }

    h = ImFmod(h, 1.0f) / (60.0f / 360.0f);
    int   i = (int)h;
    float f = h - (float)i;
    float p = v * (1.0f - s);
    float q = v * (1.0f - s * f);
    float t = v * (1.0f - s * (1.0f - f));

    switch (i)
    {
    case 0: out_r = v; out_g = t; out_b = p; break;
    case 1: out_r = q; out_g = v; out_b = p; break;
    case 2: out_r = p; out_g = v; out_b = t; break;
    case 3: out_r = p; out_g = q; out_b = v; break;
    case 4: out_r = t; out_g = p; out_b = v; break;
    case 5: default: out_r = v; out_g = p; out_b = q; break;
    }
}

//-----------------------------------------------------------------------------
// [SECTION] ImGuiStorage
// Helper: Key->value storage
//-----------------------------------------------------------------------------

// std::lower_bound but without the bullshit
static ImGuiStorage::ImGuiStoragePair* LowerBound(ImVector<ImGuiStorage::ImGuiStoragePair>& data, ImGuiID key)
{
    ImGuiStorage::ImGuiStoragePair* first = data.Data;
    ImGuiStorage::ImGuiStoragePair* last = data.Data + data.Size;
    size_t count = (size_t)(last - first);
    while (count > 0)
    {
        size_t count2 = count >> 1;
        ImGuiStorage::ImGuiStoragePair* mid = first + count2;
        if (mid->key < key)
        {
            first = ++mid;
            count -= count2 + 1;
        }
        else
        {
            count = count2;
        }
    }
    return first;
}

// For quicker full rebuild of a storage (instead of an incremental one), you may add all your contents and then sort once.
void ImGuiStorage::BuildSortByKey()
{
    struct StaticFunc
    {
        static int IMGUI_CDECL PairComparerByID(const void* lhs, const void* rhs)
        {
            // We can't just do a subtraction because qsort uses signed integers and subtracting our ID doesn't play well with that.
            if (((const ImGuiStoragePair*)lhs)->key > ((const ImGuiStoragePair*)rhs)->key) return +1;
            if (((const ImGuiStoragePair*)lhs)->key < ((const ImGuiStoragePair*)rhs)->key) return -1;
            return 0;
        }
    };
    ImQsort(Data.Data, (size_t)Data.Size, sizeof(ImGuiStoragePair), StaticFunc::PairComparerByID);
}

int ImGuiStorage::GetInt(ImGuiID key, int default_val) const
{
    ImGuiStoragePair* it = LowerBound(const_cast<ImVector<ImGuiStoragePair>&>(Data), key);
    if (it == Data.end() || it->key != key)
        return default_val;
    return it->val_i;
}

bool ImGuiStorage::GetBool(ImGuiID key, bool default_val) const
{
    return GetInt(key, default_val ? 1 : 0) != 0;
}

float ImGuiStorage::GetFloat(ImGuiID key, float default_val) const
{
    ImGuiStoragePair* it = LowerBound(const_cast<ImVector<ImGuiStoragePair>&>(Data), key);
    if (it == Data.end() || it->key != key)
        return default_val;
    return it->val_f;
}

void* ImGuiStorage::GetVoidPtr(ImGuiID key) const
{
    ImGuiStoragePair* it = LowerBound(const_cast<ImVector<ImGuiStoragePair>&>(Data), key);
    if (it == Data.end() || it->key != key)
        return NULL;
    return it->val_p;
}

// References are only valid until a new value is added to the storage. Calling a Set***() function or a Get***Ref() function invalidates the pointer.
int* ImGuiStorage::GetIntRef(ImGuiID key, int default_val)
{
    ImGuiStoragePair* it = LowerBound(Data, key);
    if (it == Data.end() || it->key != key)
        it = Data.insert(it, ImGuiStoragePair(key, default_val));
    return &it->val_i;
}

bool* ImGuiStorage::GetBoolRef(ImGuiID key, bool default_val)
{
    return (bool*)GetIntRef(key, default_val ? 1 : 0);
}

float* ImGuiStorage::GetFloatRef(ImGuiID key, float default_val)
{
    ImGuiStoragePair* it = LowerBound(Data, key);
    if (it == Data.end() || it->key != key)
        it = Data.insert(it, ImGuiStoragePair(key, default_val));
    return &it->val_f;
}

void** ImGuiStorage::GetVoidPtrRef(ImGuiID key, void* default_val)
{
    ImGuiStoragePair* it = LowerBound(Data, key);
    if (it == Data.end() || it->key != key)
        it = Data.insert(it, ImGuiStoragePair(key, default_val));
    return &it->val_p;
}

// FIXME-OPT: Need a way to reuse the result of lower_bound when doing GetInt()/SetInt() - not too bad because it only happens on explicit interaction (maximum one a frame)
void ImGuiStorage::SetInt(ImGuiID key, int val)
{
    ImGuiStoragePair* it = LowerBound(Data, key);
    if (it == Data.end() || it->key != key)
        Data.insert(it, ImGuiStoragePair(key, val));
    else
        it->val_i = val;
}

void ImGuiStorage::SetBool(ImGuiID key, bool val)
{
    SetInt(key, val ? 1 : 0);
}

void ImGuiStorage::SetFloat(ImGuiID key, float val)
{
    ImGuiStoragePair* it = LowerBound(Data, key);
    if (it == Data.end() || it->key != key)
        Data.insert(it, ImGuiStoragePair(key, val));
    else
        it->val_f = val;
}

void ImGuiStorage::SetVoidPtr(ImGuiID key, void* val)
{
    ImGuiStoragePair* it = LowerBound(Data, key);
    if (it == Data.end() || it->key != key)
        Data.insert(it, ImGuiStoragePair(key, val));
    else
        it->val_p = val;
}

void ImGuiStorage::SetAllInt(int v)
{
    for (int i = 0; i < Data.Size; i++)
        Data[i].val_i = v;
}

//-----------------------------------------------------------------------------
// [SECTION] ImGuiTextFilter
//-----------------------------------------------------------------------------

// Helper: Parse and apply text filters. In format "aaaaa[,bbbb][,ccccc]"
ImGuiTextFilter::ImGuiTextFilter(const char* default_filter) //-V1077
{
    InputBuf[0] = 0;
    CountGrep = 0;
    if (default_filter)
    {
        ImStrncpy(InputBuf, default_filter, IM_ARRAYSIZE(InputBuf));
        Build();
    }
}

bool ImGuiTextFilter::Draw(const char* label, float width)
{
    if (width != 0.0f)
        ImGui::SetNextItemWidth(width);
    bool value_changed = ImGui::InputText(label, InputBuf, IM_ARRAYSIZE(InputBuf));
    if (value_changed)
        Build();
    return value_changed;
}

void ImGuiTextFilter::ImGuiTextRange::split(char separator, ImVector<ImGuiTextRange>* out) const
{
    out->resize(0);
    const char* wb = b;
    const char* we = wb;
    while (we < e)
    {
        if (*we == separator)
        {
            out->push_back(ImGuiTextRange(wb, we));
            wb = we + 1;
        }
        we++;
    }
    if (wb != we)
        out->push_back(ImGuiTextRange(wb, we));
}

void ImGuiTextFilter::Build()
{
    Filters.resize(0);
    ImGuiTextRange input_range(InputBuf, InputBuf + strlen(InputBuf));
    input_range.split(',', &Filters);

    CountGrep = 0;
    for (ImGuiTextRange& f : Filters)
    {
        while (f.b < f.e && ImCharIsBlankA(f.b[0]))
            f.b++;
        while (f.e > f.b && ImCharIsBlankA(f.e[-1]))
            f.e--;
        if (f.empty())
            continue;
        if (f.b[0] != '-')
            CountGrep += 1;
    }
}

bool ImGuiTextFilter::PassFilter(const char* text, const char* text_end) const
{
    if (Filters.empty())
        return true;

    if (text == NULL)
        text = "";

    for (const ImGuiTextRange& f : Filters)
    {
        if (f.empty())
            continue;
        if (f.b[0] == '-')
        {
            // Subtract
            if (ImStristr(text, text_end, f.b + 1, f.e) != NULL)
                return false;
        }
        else
        {
            // Grep
            if (ImStristr(text, text_end, f.b, f.e) != NULL)
                return true;
        }
    }

    // Implicit * grep
    if (CountGrep == 0)
        return true;

    return false;
}

//-----------------------------------------------------------------------------
// [SECTION] ImGuiTextBuffer, ImGuiTextIndex
//-----------------------------------------------------------------------------

// On some platform vsnprintf() takes va_list by reference and modifies it.
// va_copy is the 'correct' way to copy a va_list but Visual Studio prior to 2013 doesn't have it.
#ifndef va_copy
#if defined(__GNUC__) || defined(__clang__)
#define va_copy(dest, src) __builtin_va_copy(dest, src)
#else
#define va_copy(dest, src) (dest = src)
#endif
#endif

char ImGuiTextBuffer::EmptyString[1] = { 0 };

void ImGuiTextBuffer::append(const char* str, const char* str_end)
{
    int len = str_end ? (int)(str_end - str) : (int)strlen(str);

    // Add zero-terminator the first time
    const int write_off = (Buf.Size != 0) ? Buf.Size : 1;
    const int needed_sz = write_off + len;
    if (write_off + len >= Buf.Capacity)
    {
        int new_capacity = Buf.Capacity * 2;
        Buf.reserve(needed_sz > new_capacity ? needed_sz : new_capacity);
    }

    Buf.resize(needed_sz);
    memcpy(&Buf[write_off - 1], str, (size_t)len);
    Buf[write_off - 1 + len] = 0;
}

void ImGuiTextBuffer::appendf(const char* fmt, ...)
{
    va_list args;
    va_start(args, fmt);
    appendfv(fmt, args);
    va_end(args);
}

// Helper: Text buffer for logging/accumulating text
void ImGuiTextBuffer::appendfv(const char* fmt, va_list args)
{
    va_list args_copy;
    va_copy(args_copy, args);

    int len = ImFormatStringV(NULL, 0, fmt, args);         // FIXME-OPT: could do a first pass write attempt, likely successful on first pass.
    if (len <= 0)
    {
        va_end(args_copy);
        return;
    }

    // Add zero-terminator the first time
    const int write_off = (Buf.Size != 0) ? Buf.Size : 1;
    const int needed_sz = write_off + len;
    if (write_off + len >= Buf.Capacity)
    {
        int new_capacity = Buf.Capacity * 2;
        Buf.reserve(needed_sz > new_capacity ? needed_sz : new_capacity);
    }

    Buf.resize(needed_sz);
    ImFormatStringV(&Buf[write_off - 1], (size_t)len + 1, fmt, args_copy);
    va_end(args_copy);
}

void ImGuiTextIndex::append(const char* base, int old_size, int new_size)
{
    IM_ASSERT(old_size >= 0 && new_size >= old_size && new_size >= EndOffset);
    if (old_size == new_size)
        return;
    if (EndOffset == 0 || base[EndOffset - 1] == '\n')
        LineOffsets.push_back(EndOffset);
    const char* base_end = base + new_size;
    for (const char* p = base + old_size; (p = (const char*)memchr(p, '\n', base_end - p)) != 0; )
        if (++p < base_end) // Don't push a trailing offset on last \n
            LineOffsets.push_back((int)(intptr_t)(p - base));
    EndOffset = ImMax(EndOffset, new_size);
}

//-----------------------------------------------------------------------------
// [SECTION] ImGuiListClipper
//-----------------------------------------------------------------------------

// FIXME-TABLE: This prevents us from using ImGuiListClipper _inside_ a table cell.
// The problem we have is that without a Begin/End scheme for rows using the clipper is ambiguous.
static bool GetSkipItemForListClipping()
{
    ImGuiContext& g = *GImGui;
    return (g.CurrentTable ? g.CurrentTable->HostSkipItems : g.CurrentWindow->SkipItems);
}

#ifndef IMGUI_DISABLE_OBSOLETE_FUNCTIONS
// Legacy helper to calculate coarse clipping of large list of evenly sized items.
// This legacy API is not ideal because it assumes we will return a single contiguous rectangle.
// Prefer using ImGuiListClipper which can returns non-contiguous ranges.
void ImGui::CalcListClipping(int items_count, float items_height, int* out_items_display_start, int* out_items_display_end)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    if (g.LogEnabled)
    {
        // If logging is active, do not perform any clipping
        *out_items_display_start = 0;
        *out_items_display_end = items_count;
        return;
    }
    if (GetSkipItemForListClipping())
    {
        *out_items_display_start = *out_items_display_end = 0;
        return;
    }

    // We create the union of the ClipRect and the scoring rect which at worst should be 1 page away from ClipRect
    // We don't include g.NavId's rectangle in there (unless g.NavJustMovedToId is set) because the rectangle enlargement can get costly.
    ImRect rect = window->ClipRect;
    if (g.NavMoveScoringItems)
        rect.Add(g.NavScoringNoClipRect);
    if (g.NavJustMovedToId && window->NavLastIds[0] == g.NavJustMovedToId)
        rect.Add(WindowRectRelToAbs(window, window->NavRectRel[0])); // Could store and use NavJustMovedToRectRel

    const ImVec2 pos = window->DC.CursorPos;
    int start = (int)((rect.Min.y - pos.y) / items_height);
    int end = (int)((rect.Max.y - pos.y) / items_height);

    // When performing a navigation request, ensure we have one item extra in the direction we are moving to
    // FIXME: Verify this works with tabbing
    const bool is_nav_request = (g.NavMoveScoringItems && g.NavWindow && g.NavWindow->RootWindowForNav == window->RootWindowForNav);
    if (is_nav_request && g.NavMoveClipDir == ImGuiDir_Up)
        start--;
    if (is_nav_request && g.NavMoveClipDir == ImGuiDir_Down)
        end++;

    start = ImClamp(start, 0, items_count);
    end = ImClamp(end + 1, start, items_count);
    *out_items_display_start = start;
    *out_items_display_end = end;
}
#endif

static void ImGuiListClipper_SortAndFuseRanges(ImVector<ImGuiListClipperRange>& ranges, int offset = 0)
{
    if (ranges.Size - offset <= 1)
        return;

    // Helper to order ranges and fuse them together if possible (bubble sort is fine as we are only sorting 2-3 entries)
    for (int sort_end = ranges.Size - offset - 1; sort_end > 0; --sort_end)
        for (int i = offset; i < sort_end + offset; ++i)
            if (ranges[i].Min > ranges[i + 1].Min)
                ImSwap(ranges[i], ranges[i + 1]);

    // Now fuse ranges together as much as possible.
    for (int i = 1 + offset; i < ranges.Size; i++)
    {
        IM_ASSERT(!ranges[i].PosToIndexConvert && !ranges[i - 1].PosToIndexConvert);
        if (ranges[i - 1].Max < ranges[i].Min)
            continue;
        ranges[i - 1].Min = ImMin(ranges[i - 1].Min, ranges[i].Min);
        ranges[i - 1].Max = ImMax(ranges[i - 1].Max, ranges[i].Max);
        ranges.erase(ranges.Data + i);
        i--;
    }
}

static void ImGuiListClipper_SeekCursorAndSetupPrevLine(float pos_y, float line_height)
{
    // Set cursor position and a few other things so that SetScrollHereY() and Columns() can work when seeking cursor.
    // FIXME: It is problematic that we have to do that here, because custom/equivalent end-user code would stumble on the same issue.
    // The clipper should probably have a final step to display the last item in a regular manner, maybe with an opt-out flag for data sets which may have costly seek?
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    float off_y = pos_y - window->DC.CursorPos.y;
    window->DC.CursorPos.y = pos_y;
    window->DC.CursorMaxPos.y = ImMax(window->DC.CursorMaxPos.y, pos_y - g.Style.ItemSpacing.y);
    window->DC.CursorPosPrevLine.y = window->DC.CursorPos.y - line_height;  // Setting those fields so that SetScrollHereY() can properly function after the end of our clipper usage.
    window->DC.PrevLineSize.y = (line_height - g.Style.ItemSpacing.y);      // If we end up needing more accurate data (to e.g. use SameLine) we may as well make the clipper have a fourth step to let user process and display the last item in their list.
    if (ImGuiOldColumns* columns = window->DC.CurrentColumns)
        columns->LineMinY = window->DC.CursorPos.y;                         // Setting this so that cell Y position are set properly
    if (ImGuiTable* table = g.CurrentTable)
    {
        if (table->IsInsideRow)
            ImGui::TableEndRow(table);
        table->RowPosY2 = window->DC.CursorPos.y;
        const int row_increase = (int)((off_y / line_height) + 0.5f);
        //table->CurrentRow += row_increase; // Can't do without fixing TableEndRow()
        table->RowBgColorCounter += row_increase;
    }
}

static void ImGuiListClipper_SeekCursorForItem(ImGuiListClipper* clipper, int item_n)
{
    // StartPosY starts from ItemsFrozen hence the subtraction
    // Perform the add and multiply with double to allow seeking through larger ranges
    ImGuiListClipperData* data = (ImGuiListClipperData*)clipper->TempData;
    float pos_y = (float)((double)clipper->StartPosY + data->LossynessOffset + (double)(item_n - data->ItemsFrozen) * clipper->ItemsHeight);
    ImGuiListClipper_SeekCursorAndSetupPrevLine(pos_y, clipper->ItemsHeight);
}

ImGuiListClipper::ImGuiListClipper()
{
    memset(this, 0, sizeof(*this));
}

ImGuiListClipper::~ImGuiListClipper()
{
    End();
}

void ImGuiListClipper::Begin(int items_count, float items_height)
{
    if (Ctx == NULL)
        Ctx = ImGui::GetCurrentContext();

    ImGuiContext& g = *Ctx;
    ImGuiWindow* window = g.CurrentWindow;
    IMGUI_DEBUG_LOG_CLIPPER("Clipper: Begin(%d,%.2f) in '%s'\n", items_count, items_height, window->Name);

    if (ImGuiTable* table = g.CurrentTable)
        if (table->IsInsideRow)
            ImGui::TableEndRow(table);

    StartPosY = window->DC.CursorPos.y;
    ItemsHeight = items_height;
    ItemsCount = items_count;
    DisplayStart = -1;
    DisplayEnd = 0;

    // Acquire temporary buffer
    if (++g.ClipperTempDataStacked > g.ClipperTempData.Size)
        g.ClipperTempData.resize(g.ClipperTempDataStacked, ImGuiListClipperData());
    ImGuiListClipperData* data = &g.ClipperTempData[g.ClipperTempDataStacked - 1];
    data->Reset(this);
    data->LossynessOffset = window->DC.CursorStartPosLossyness.y;
    TempData = data;
}

void ImGuiListClipper::End()
{
    if (ImGuiListClipperData* data = (ImGuiListClipperData*)TempData)
    {
        // In theory here we should assert that we are already at the right position, but it seems saner to just seek at the end and not assert/crash the user.
        ImGuiContext& g = *Ctx;
        IMGUI_DEBUG_LOG_CLIPPER("Clipper: End() in '%s'\n", g.CurrentWindow->Name);
        if (ItemsCount >= 0 && ItemsCount < INT_MAX && DisplayStart >= 0)
            ImGuiListClipper_SeekCursorForItem(this, ItemsCount);

        // Restore temporary buffer and fix back pointers which may be invalidated when nesting
        IM_ASSERT(data->ListClipper == this);
        data->StepNo = data->Ranges.Size;
        if (--g.ClipperTempDataStacked > 0)
        {
            data = &g.ClipperTempData[g.ClipperTempDataStacked - 1];
            data->ListClipper->TempData = data;
        }
        TempData = NULL;
    }
    ItemsCount = -1;
}

void ImGuiListClipper::IncludeItemsByIndex(int item_begin, int item_end)
{
    ImGuiListClipperData* data = (ImGuiListClipperData*)TempData;
    IM_ASSERT(DisplayStart < 0); // Only allowed after Begin() and if there has not been a specified range yet.
    IM_ASSERT(item_begin <= item_end);
    if (item_begin < item_end)
        data->Ranges.push_back(ImGuiListClipperRange::FromIndices(item_begin, item_end));
}

static bool ImGuiListClipper_StepInternal(ImGuiListClipper* clipper)
{
    ImGuiContext& g = *clipper->Ctx;
    ImGuiWindow* window = g.CurrentWindow;
    ImGuiListClipperData* data = (ImGuiListClipperData*)clipper->TempData;
    IM_ASSERT(data != NULL && "Called ImGuiListClipper::Step() too many times, or before ImGuiListClipper::Begin() ?");

    ImGuiTable* table = g.CurrentTable;
    if (table && table->IsInsideRow)
        ImGui::TableEndRow(table);

    // No items
    if (clipper->ItemsCount == 0 || GetSkipItemForListClipping())
        return false;

    // While we are in frozen row state, keep displaying items one by one, unclipped
    // FIXME: Could be stored as a table-agnostic state.
    if (data->StepNo == 0 && table != NULL && !table->IsUnfrozenRows)
    {
        clipper->DisplayStart = data->ItemsFrozen;
        clipper->DisplayEnd = ImMin(data->ItemsFrozen + 1, clipper->ItemsCount);
        if (clipper->DisplayStart < clipper->DisplayEnd)
            data->ItemsFrozen++;
        return true;
    }

    // Step 0: Let you process the first element (regardless of it being visible or not, so we can measure the element height)
    bool calc_clipping = false;
    if (data->StepNo == 0)
    {
        clipper->StartPosY = window->DC.CursorPos.y;
        if (clipper->ItemsHeight <= 0.0f)
        {
            // Submit the first item (or range) so we can measure its height (generally the first range is 0..1)
            data->Ranges.push_front(ImGuiListClipperRange::FromIndices(data->ItemsFrozen, data->ItemsFrozen + 1));
            clipper->DisplayStart = ImMax(data->Ranges[0].Min, data->ItemsFrozen);
            clipper->DisplayEnd = ImMin(data->Ranges[0].Max, clipper->ItemsCount);
            data->StepNo = 1;
            return true;
        }
        calc_clipping = true;   // If on the first step with known item height, calculate clipping.
    }

    // Step 1: Let the clipper infer height from first range
    if (clipper->ItemsHeight <= 0.0f)
    {
        IM_ASSERT(data->StepNo == 1);
        if (table)
            IM_ASSERT(table->RowPosY1 == clipper->StartPosY && table->RowPosY2 == window->DC.CursorPos.y);

        clipper->ItemsHeight = (window->DC.CursorPos.y - clipper->StartPosY) / (float)(clipper->DisplayEnd - clipper->DisplayStart);
        bool affected_by_floating_point_precision = ImIsFloatAboveGuaranteedIntegerPrecision(clipper->StartPosY) || ImIsFloatAboveGuaranteedIntegerPrecision(window->DC.CursorPos.y);
        if (affected_by_floating_point_precision)
            clipper->ItemsHeight = window->DC.PrevLineSize.y + g.Style.ItemSpacing.y; // FIXME: Technically wouldn't allow multi-line entries.

        IM_ASSERT(clipper->ItemsHeight > 0.0f && "Unable to calculate item height! First item hasn't moved the cursor vertically!");
        calc_clipping = true;   // If item height had to be calculated, calculate clipping afterwards.
    }

    // Step 0 or 1: Calculate the actual ranges of visible elements.
    const int already_submitted = clipper->DisplayEnd;
    if (calc_clipping)
    {
        if (g.LogEnabled)
        {
            // If logging is active, do not perform any clipping
            data->Ranges.push_back(ImGuiListClipperRange::FromIndices(0, clipper->ItemsCount));
        }
        else
        {
            // Add range selected to be included for navigation
            const bool is_nav_request = (g.NavMoveScoringItems && g.NavWindow && g.NavWindow->RootWindowForNav == window->RootWindowForNav);
            if (is_nav_request)
                data->Ranges.push_back(ImGuiListClipperRange::FromPositions(g.NavScoringNoClipRect.Min.y, g.NavScoringNoClipRect.Max.y, 0, 0));
            if (is_nav_request && (g.NavMoveFlags & ImGuiNavMoveFlags_IsTabbing) && g.NavTabbingDir == -1)
                data->Ranges.push_back(ImGuiListClipperRange::FromIndices(clipper->ItemsCount - 1, clipper->ItemsCount));

            // Add focused/active item
            ImRect nav_rect_abs = ImGui::WindowRectRelToAbs(window, window->NavRectRel[0]);
            if (g.NavId != 0 && window->NavLastIds[0] == g.NavId)
                data->Ranges.push_back(ImGuiListClipperRange::FromPositions(nav_rect_abs.Min.y, nav_rect_abs.Max.y, 0, 0));

            // Add visible range
            const int off_min = (is_nav_request && g.NavMoveClipDir == ImGuiDir_Up) ? -1 : 0;
            const int off_max = (is_nav_request && g.NavMoveClipDir == ImGuiDir_Down) ? 1 : 0;
            data->Ranges.push_back(ImGuiListClipperRange::FromPositions(window->ClipRect.Min.y, window->ClipRect.Max.y, off_min, off_max));
        }

        // Convert position ranges to item index ranges
        // - Very important: when a starting position is after our maximum item, we set Min to (ItemsCount - 1). This allows us to handle most forms of wrapping.
        // - Due to how Selectable extra padding they tend to be "unaligned" with exact unit in the item list,
        //   which with the flooring/ceiling tend to lead to 2 items instead of one being submitted.
        for (ImGuiListClipperRange& range : data->Ranges)
            if (range.PosToIndexConvert)
            {
                int m1 = (int)(((double)range.Min - window->DC.CursorPos.y - data->LossynessOffset) / clipper->ItemsHeight);
                int m2 = (int)((((double)range.Max - window->DC.CursorPos.y - data->LossynessOffset) / clipper->ItemsHeight) + 0.999999f);
                range.Min = ImClamp(already_submitted + m1 + range.PosToIndexOffsetMin, already_submitted, clipper->ItemsCount - 1);
                range.Max = ImClamp(already_submitted + m2 + range.PosToIndexOffsetMax, range.Min + 1, clipper->ItemsCount);
                range.PosToIndexConvert = false;
            }
        ImGuiListClipper_SortAndFuseRanges(data->Ranges, data->StepNo);
    }

    // Step 0+ (if item height is given in advance) or 1+: Display the next range in line.
    while (data->StepNo < data->Ranges.Size)
    {
        clipper->DisplayStart = ImMax(data->Ranges[data->StepNo].Min, already_submitted);
        clipper->DisplayEnd = ImMin(data->Ranges[data->StepNo].Max, clipper->ItemsCount);
        if (clipper->DisplayStart > already_submitted) //-V1051
            ImGuiListClipper_SeekCursorForItem(clipper, clipper->DisplayStart);
        data->StepNo++;
        if (clipper->DisplayStart == clipper->DisplayEnd && data->StepNo < data->Ranges.Size)
            continue;
        return true;
    }

    // After the last step: Let the clipper validate that we have reached the expected Y position (corresponding to element DisplayEnd),
    // Advance the cursor to the end of the list and then returns 'false' to end the loop.
    if (clipper->ItemsCount < INT_MAX)
        ImGuiListClipper_SeekCursorForItem(clipper, clipper->ItemsCount);

    return false;
}

bool ImGuiListClipper::Step()
{
    ImGuiContext& g = *Ctx;
    bool need_items_height = (ItemsHeight <= 0.0f);
    bool ret = ImGuiListClipper_StepInternal(this);
    if (ret && (DisplayStart == DisplayEnd))
        ret = false;
    if (g.CurrentTable && g.CurrentTable->IsUnfrozenRows == false)
        IMGUI_DEBUG_LOG_CLIPPER("Clipper: Step(): inside frozen table row.\n");
    if (need_items_height && ItemsHeight > 0.0f)
        IMGUI_DEBUG_LOG_CLIPPER("Clipper: Step(): computed ItemsHeight: %.2f.\n", ItemsHeight);
    if (ret)
    {
        IMGUI_DEBUG_LOG_CLIPPER("Clipper: Step(): display %d to %d.\n", DisplayStart, DisplayEnd);
    }
    else
    {
        IMGUI_DEBUG_LOG_CLIPPER("Clipper: Step(): End.\n");
        End();
    }
    return ret;
}

//-----------------------------------------------------------------------------
// [SECTION] STYLING
//-----------------------------------------------------------------------------

ImGuiStyle& ImGui::GetStyle()
{
    IM_ASSERT(GImGui != NULL && "No current context. Did you call ImGui::CreateContext() and ImGui::SetCurrentContext() ?");
    return GImGui->Style;
}

ImU32 ImGui::GetColorU32(ImGuiCol idx, float alpha_mul)
{
    ImGuiStyle& style = GImGui->Style;
    ImVec4 c = style.Colors[idx];
    c.w *= style.Alpha * alpha_mul;
    return ColorConvertFloat4ToU32(c);
}

ImU32 ImGui::GetColorU32(const ImVec4& col)
{
    ImGuiStyle& style = GImGui->Style;
    ImVec4 c = col;
    c.w *= style.Alpha;
    return ColorConvertFloat4ToU32(c);
}

const ImVec4& ImGui::GetStyleColorVec4(ImGuiCol idx)
{
    ImGuiStyle& style = GImGui->Style;
    return style.Colors[idx];
}

ImU32 ImGui::GetColorU32(ImU32 col)
{
    ImGuiStyle& style = GImGui->Style;
    if (style.Alpha >= 1.0f)
        return col;
    ImU32 a = (col & IM_COL32_A_MASK) >> IM_COL32_A_SHIFT;
    a = (ImU32)(a * style.Alpha); // We don't need to clamp 0..255 because Style.Alpha is in 0..1 range.
    return (col & ~IM_COL32_A_MASK) | (a << IM_COL32_A_SHIFT);
}

// FIXME: This may incur a round-trip (if the end user got their data from a float4) but eventually we aim to store the in-flight colors as ImU32
void ImGui::PushStyleColor(ImGuiCol idx, ImU32 col)
{
    ImGuiContext& g = *GImGui;
    ImGuiColorMod backup;
    backup.Col = idx;
    backup.BackupValue = g.Style.Colors[idx];
    g.ColorStack.push_back(backup);
    g.Style.Colors[idx] = ColorConvertU32ToFloat4(col);
}

void ImGui::PushStyleColor(ImGuiCol idx, const ImVec4& col)
{
    ImGuiContext& g = *GImGui;
    ImGuiColorMod backup;
    backup.Col = idx;
    backup.BackupValue = g.Style.Colors[idx];
    g.ColorStack.push_back(backup);
    g.Style.Colors[idx] = col;
}

void ImGui::PopStyleColor(int count)
{
    ImGuiContext& g = *GImGui;
    if (g.ColorStack.Size < count)
    {
        IM_ASSERT_USER_ERROR(g.ColorStack.Size > count, "Calling PopStyleColor() too many times: stack underflow.");
        count = g.ColorStack.Size;
    }
    while (count > 0)
    {
        ImGuiColorMod& backup = g.ColorStack.back();
        g.Style.Colors[backup.Col] = backup.BackupValue;
        g.ColorStack.pop_back();
        count--;
    }
}

static const ImGuiCol GWindowDockStyleColors[ImGuiWindowDockStyleCol_COUNT] =
{
    ImGuiCol_Text, ImGuiCol_Tab, ImGuiCol_TabHovered, ImGuiCol_TabActive, ImGuiCol_TabUnfocused, ImGuiCol_TabUnfocusedActive
};

static const ImGuiDataVarInfo GStyleVarInfo[] =
{
    { ImGuiDataType_Float, 1, (ImU32)offsetof(ImGuiStyle, Alpha) },                 // ImGuiStyleVar_Alpha
    { ImGuiDataType_Float, 1, (ImU32)offsetof(ImGuiStyle, DisabledAlpha) },         // ImGuiStyleVar_DisabledAlpha
    { ImGuiDataType_Float, 2, (ImU32)offsetof(ImGuiStyle, WindowPadding) },         // ImGuiStyleVar_WindowPadding
    { ImGuiDataType_Float, 1, (ImU32)offsetof(ImGuiStyle, WindowRounding) },        // ImGuiStyleVar_WindowRounding
    { ImGuiDataType_Float, 1, (ImU32)offsetof(ImGuiStyle, WindowBorderSize) },      // ImGuiStyleVar_WindowBorderSize
    { ImGuiDataType_Float, 2, (ImU32)offsetof(ImGuiStyle, WindowMinSize) },         // ImGuiStyleVar_WindowMinSize
    { ImGuiDataType_Float, 2, (ImU32)offsetof(ImGuiStyle, WindowTitleAlign) },      // ImGuiStyleVar_WindowTitleAlign
    { ImGuiDataType_Float, 1, (ImU32)offsetof(ImGuiStyle, ChildRounding) },         // ImGuiStyleVar_ChildRounding
    { ImGuiDataType_Float, 1, (ImU32)offsetof(ImGuiStyle, ChildBorderSize) },       // ImGuiStyleVar_ChildBorderSize
    { ImGuiDataType_Float, 1, (ImU32)offsetof(ImGuiStyle, PopupRounding) },         // ImGuiStyleVar_PopupRounding
    { ImGuiDataType_Float, 1, (ImU32)offsetof(ImGuiStyle, PopupBorderSize) },       // ImGuiStyleVar_PopupBorderSize
    { ImGuiDataType_Float, 2, (ImU32)offsetof(ImGuiStyle, FramePadding) },          // ImGuiStyleVar_FramePadding
    { ImGuiDataType_Float, 1, (ImU32)offsetof(ImGuiStyle, FrameRounding) },         // ImGuiStyleVar_FrameRounding
    { ImGuiDataType_Float, 1, (ImU32)offsetof(ImGuiStyle, FrameBorderSize) },       // ImGuiStyleVar_FrameBorderSize
    { ImGuiDataType_Float, 2, (ImU32)offsetof(ImGuiStyle, ItemSpacing) },           // ImGuiStyleVar_ItemSpacing
    { ImGuiDataType_Float, 2, (ImU32)offsetof(ImGuiStyle, ItemInnerSpacing) },      // ImGuiStyleVar_ItemInnerSpacing
    { ImGuiDataType_Float, 1, (ImU32)offsetof(ImGuiStyle, IndentSpacing) },         // ImGuiStyleVar_IndentSpacing
    { ImGuiDataType_Float, 2, (ImU32)offsetof(ImGuiStyle, CellPadding) },           // ImGuiStyleVar_CellPadding
    { ImGuiDataType_Float, 1, (ImU32)offsetof(ImGuiStyle, ScrollbarSize) },         // ImGuiStyleVar_ScrollbarSize
    { ImGuiDataType_Float, 1, (ImU32)offsetof(ImGuiStyle, ScrollbarRounding) },     // ImGuiStyleVar_ScrollbarRounding
    { ImGuiDataType_Float, 1, (ImU32)offsetof(ImGuiStyle, GrabMinSize) },           // ImGuiStyleVar_GrabMinSize
    { ImGuiDataType_Float, 1, (ImU32)offsetof(ImGuiStyle, GrabRounding) },          // ImGuiStyleVar_GrabRounding
    { ImGuiDataType_Float, 1, (ImU32)offsetof(ImGuiStyle, TabRounding) },           // ImGuiStyleVar_TabRounding
    { ImGuiDataType_Float, 1, (ImU32)offsetof(ImGuiStyle, TabBarBorderSize) },      // ImGuiStyleVar_TabBarBorderSize
    { ImGuiDataType_Float, 2, (ImU32)offsetof(ImGuiStyle, ButtonTextAlign) },       // ImGuiStyleVar_ButtonTextAlign
    { ImGuiDataType_Float, 2, (ImU32)offsetof(ImGuiStyle, SelectableTextAlign) },   // ImGuiStyleVar_SelectableTextAlign
    { ImGuiDataType_Float, 1, (ImU32)offsetof(ImGuiStyle, SeparatorTextBorderSize) },// ImGuiStyleVar_SeparatorTextBorderSize
    { ImGuiDataType_Float, 2, (ImU32)offsetof(ImGuiStyle, SeparatorTextAlign) },    // ImGuiStyleVar_SeparatorTextAlign
    { ImGuiDataType_Float, 2, (ImU32)offsetof(ImGuiStyle, SeparatorTextPadding) },  // ImGuiStyleVar_SeparatorTextPadding
    { ImGuiDataType_Float, 1, (ImU32)offsetof(ImGuiStyle, DockingSeparatorSize) },  // ImGuiStyleVar_DockingSeparatorSize
};

const ImGuiDataVarInfo* ImGui::GetStyleVarInfo(ImGuiStyleVar idx)
{
    IM_ASSERT(idx >= 0 && idx < ImGuiStyleVar_COUNT);
    IM_STATIC_ASSERT(IM_ARRAYSIZE(GStyleVarInfo) == ImGuiStyleVar_COUNT);
    return &GStyleVarInfo[idx];
}

void ImGui::PushStyleVar(ImGuiStyleVar idx, float val)
{
    ImGuiContext& g = *GImGui;
    const ImGuiDataVarInfo* var_info = GetStyleVarInfo(idx);
    if (var_info->Type == ImGuiDataType_Float && var_info->Count == 1)
    {
        float* pvar = (float*)var_info->GetVarPtr(&g.Style);
        g.StyleVarStack.push_back(ImGuiStyleMod(idx, *pvar));
        *pvar = val;
        return;
    }
    IM_ASSERT_USER_ERROR(0, "Called PushStyleVar() variant with wrong type!");
}

void ImGui::PushStyleVar(ImGuiStyleVar idx, const ImVec2& val)
{
    ImGuiContext& g = *GImGui;
    const ImGuiDataVarInfo* var_info = GetStyleVarInfo(idx);
    if (var_info->Type == ImGuiDataType_Float && var_info->Count == 2)
    {
        ImVec2* pvar = (ImVec2*)var_info->GetVarPtr(&g.Style);
        g.StyleVarStack.push_back(ImGuiStyleMod(idx, *pvar));
        *pvar = val;
        return;
    }
    IM_ASSERT_USER_ERROR(0, "Called PushStyleVar() variant with wrong type!");
}

void ImGui::PopStyleVar(int count)
{
    ImGuiContext& g = *GImGui;
    if (g.StyleVarStack.Size < count)
    {
        IM_ASSERT_USER_ERROR(g.StyleVarStack.Size > count, "Calling PopStyleVar() too many times: stack underflow.");
        count = g.StyleVarStack.Size;
    }
    while (count > 0)
    {
        // We avoid a generic memcpy(data, &backup.Backup.., GDataTypeSize[info->Type] * info->Count), the overhead in Debug is not worth it.
        ImGuiStyleMod& backup = g.StyleVarStack.back();
        const ImGuiDataVarInfo* info = GetStyleVarInfo(backup.VarIdx);
        void* data = info->GetVarPtr(&g.Style);
        if (info->Type == ImGuiDataType_Float && info->Count == 1)      { ((float*)data)[0] = backup.BackupFloat[0]; }
        else if (info->Type == ImGuiDataType_Float && info->Count == 2) { ((float*)data)[0] = backup.BackupFloat[0]; ((float*)data)[1] = backup.BackupFloat[1]; }
        g.StyleVarStack.pop_back();
        count--;
    }
}

const char* ImGui::GetStyleColorName(ImGuiCol idx)
{
    // Create switch-case from enum with regexp: ImGuiCol_{.*}, --> case ImGuiCol_\1: return "\1";
    switch (idx)
    {
    case ImGuiCol_Text: return "Text";
    case ImGuiCol_TextDisabled: return "TextDisabled";
    case ImGuiCol_WindowBg: return "WindowBg";
    case ImGuiCol_ChildBg: return "ChildBg";
    case ImGuiCol_PopupBg: return "PopupBg";
    case ImGuiCol_Border: return "Border";
    case ImGuiCol_BorderShadow: return "BorderShadow";
    case ImGuiCol_FrameBg: return "FrameBg";
    case ImGuiCol_FrameBgHovered: return "FrameBgHovered";
    case ImGuiCol_FrameBgActive: return "FrameBgActive";
    case ImGuiCol_TitleBg: return "TitleBg";
    case ImGuiCol_TitleBgActive: return "TitleBgActive";
    case ImGuiCol_TitleBgCollapsed: return "TitleBgCollapsed";
    case ImGuiCol_MenuBarBg: return "MenuBarBg";
    case ImGuiCol_ScrollbarBg: return "ScrollbarBg";
    case ImGuiCol_ScrollbarGrab: return "ScrollbarGrab";
    case ImGuiCol_ScrollbarGrabHovered: return "ScrollbarGrabHovered";
    case ImGuiCol_ScrollbarGrabActive: return "ScrollbarGrabActive";
    case ImGuiCol_CheckMark: return "CheckMark";
    case ImGuiCol_SliderGrab: return "SliderGrab";
    case ImGuiCol_SliderGrabActive: return "SliderGrabActive";
    case ImGuiCol_Button: return "Button";
    case ImGuiCol_ButtonHovered: return "ButtonHovered";
    case ImGuiCol_ButtonActive: return "ButtonActive";
    case ImGuiCol_Header: return "Header";
    case ImGuiCol_HeaderHovered: return "HeaderHovered";
    case ImGuiCol_HeaderActive: return "HeaderActive";
    case ImGuiCol_Separator: return "Separator";
    case ImGuiCol_SeparatorHovered: return "SeparatorHovered";
    case ImGuiCol_SeparatorActive: return "SeparatorActive";
    case ImGuiCol_ResizeGrip: return "ResizeGrip";
    case ImGuiCol_ResizeGripHovered: return "ResizeGripHovered";
    case ImGuiCol_ResizeGripActive: return "ResizeGripActive";
    case ImGuiCol_Tab: return "Tab";
    case ImGuiCol_TabHovered: return "TabHovered";
    case ImGuiCol_TabActive: return "TabActive";
    case ImGuiCol_TabUnfocused: return "TabUnfocused";
    case ImGuiCol_TabUnfocusedActive: return "TabUnfocusedActive";
    case ImGuiCol_DockingPreview: return "DockingPreview";
    case ImGuiCol_DockingEmptyBg: return "DockingEmptyBg";
    case ImGuiCol_PlotLines: return "PlotLines";
    case ImGuiCol_PlotLinesHovered: return "PlotLinesHovered";
    case ImGuiCol_PlotHistogram: return "PlotHistogram";
    case ImGuiCol_PlotHistogramHovered: return "PlotHistogramHovered";
    case ImGuiCol_TableHeaderBg: return "TableHeaderBg";
    case ImGuiCol_TableBorderStrong: return "TableBorderStrong";
    case ImGuiCol_TableBorderLight: return "TableBorderLight";
    case ImGuiCol_TableRowBg: return "TableRowBg";
    case ImGuiCol_TableRowBgAlt: return "TableRowBgAlt";
    case ImGuiCol_TextSelectedBg: return "TextSelectedBg";
    case ImGuiCol_DragDropTarget: return "DragDropTarget";
    case ImGuiCol_NavHighlight: return "NavHighlight";
    case ImGuiCol_NavWindowingHighlight: return "NavWindowingHighlight";
    case ImGuiCol_NavWindowingDimBg: return "NavWindowingDimBg";
    case ImGuiCol_ModalWindowDimBg: return "ModalWindowDimBg";
    }
    IM_ASSERT(0);
    return "Unknown";
}


//-----------------------------------------------------------------------------
// [SECTION] RENDER HELPERS
// Some of those (internal) functions are currently quite a legacy mess - their signature and behavior will change,
// we need a nicer separation between low-level functions and high-level functions relying on the ImGui context.
// Also see imgui_draw.cpp for some more which have been reworked to not rely on ImGui:: context.
//-----------------------------------------------------------------------------

const char* ImGui::FindRenderedTextEnd(const char* text, const char* text_end)
{
    const char* text_display_end = text;
    if (!text_end)
        text_end = (const char*)-1;

    while (text_display_end < text_end && *text_display_end != '\0' && (text_display_end[0] != '#' || text_display_end[1] != '#'))
        text_display_end++;
    return text_display_end;
}

// Internal ImGui functions to render text
// RenderText***() functions calls ImDrawList::AddText() calls ImBitmapFont::RenderText()
void ImGui::RenderText(ImVec2 pos, const char* text, const char* text_end, bool hide_text_after_hash)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;

    // Hide anything after a '##' string
    const char* text_display_end;
    if (hide_text_after_hash)
    {
        text_display_end = FindRenderedTextEnd(text, text_end);
    }
    else
    {
        if (!text_end)
            text_end = text + strlen(text); // FIXME-OPT
        text_display_end = text_end;
    }

    if (text != text_display_end)
    {
        window->DrawList->AddText(g.Font, g.FontSize, pos, GetColorU32(ImGuiCol_Text), text, text_display_end);
        if (g.LogEnabled)
            LogRenderedText(&pos, text, text_display_end);
    }
}

void ImGui::RenderTextWrapped(ImVec2 pos, const char* text, const char* text_end, float wrap_width)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;

    if (!text_end)
        text_end = text + strlen(text); // FIXME-OPT

    if (text != text_end)
    {
        window->DrawList->AddText(g.Font, g.FontSize, pos, GetColorU32(ImGuiCol_Text), text, text_end, wrap_width);
        if (g.LogEnabled)
            LogRenderedText(&pos, text, text_end);
    }
}

// Default clip_rect uses (pos_min,pos_max)
// Handle clipping on CPU immediately (vs typically let the GPU clip the triangles that are overlapping the clipping rectangle edges)
// FIXME-OPT: Since we have or calculate text_size we could coarse clip whole block immediately, especally for text above draw_list->DrawList.
// Effectively as this is called from widget doing their own coarse clipping it's not very valuable presently. Next time function will take
// better advantage of the render function taking size into account for coarse clipping.
void ImGui::RenderTextClippedEx(ImDrawList* draw_list, const ImVec2& pos_min, const ImVec2& pos_max, const char* text, const char* text_display_end, const ImVec2* text_size_if_known, const ImVec2& align, const ImRect* clip_rect)
{
    // Perform CPU side clipping for single clipped element to avoid using scissor state
    ImVec2 pos = pos_min;
    const ImVec2 text_size = text_size_if_known ? *text_size_if_known : CalcTextSize(text, text_display_end, false, 0.0f);

    const ImVec2* clip_min = clip_rect ? &clip_rect->Min : &pos_min;
    const ImVec2* clip_max = clip_rect ? &clip_rect->Max : &pos_max;
    bool need_clipping = (pos.x + text_size.x >= clip_max->x) || (pos.y + text_size.y >= clip_max->y);
    if (clip_rect) // If we had no explicit clipping rectangle then pos==clip_min
        need_clipping |= (pos.x < clip_min->x) || (pos.y < clip_min->y);

    // Align whole block. We should defer that to the better rendering function when we'll have support for individual line alignment.
    if (align.x > 0.0f) pos.x = ImMax(pos.x, pos.x + (pos_max.x - pos.x - text_size.x) * align.x);
    if (align.y > 0.0f) pos.y = ImMax(pos.y, pos.y + (pos_max.y - pos.y - text_size.y) * align.y);

    // Render
    if (need_clipping)
    {
        ImVec4 fine_clip_rect(clip_min->x, clip_min->y, clip_max->x, clip_max->y);
        draw_list->AddText(NULL, 0.0f, pos, GetColorU32(ImGuiCol_Text), text, text_display_end, 0.0f, &fine_clip_rect);
    }
    else
    {
        draw_list->AddText(NULL, 0.0f, pos, GetColorU32(ImGuiCol_Text), text, text_display_end, 0.0f, NULL);
    }
}

void ImGui::RenderTextClipped(const ImVec2& pos_min, const ImVec2& pos_max, const char* text, const char* text_end, const ImVec2* text_size_if_known, const ImVec2& align, const ImRect* clip_rect)
{
    // Hide anything after a '##' string
    const char* text_display_end = FindRenderedTextEnd(text, text_end);
    const int text_len = (int)(text_display_end - text);
    if (text_len == 0)
        return;

    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    RenderTextClippedEx(window->DrawList, pos_min, pos_max, text, text_display_end, text_size_if_known, align, clip_rect);
    if (g.LogEnabled)
        LogRenderedText(&pos_min, text, text_display_end);
}

// Another overly complex function until we reorganize everything into a nice all-in-one helper.
// This is made more complex because we have dissociated the layout rectangle (pos_min..pos_max) which define _where_ the ellipsis is, from actual clipping of text and limit of the ellipsis display.
// This is because in the context of tabs we selectively hide part of the text when the Close Button appears, but we don't want the ellipsis to move.
void ImGui::RenderTextEllipsis(ImDrawList* draw_list, const ImVec2& pos_min, const ImVec2& pos_max, float clip_max_x, float ellipsis_max_x, const char* text, const char* text_end_full, const ImVec2* text_size_if_known)
{
    ImGuiContext& g = *GImGui;
    if (text_end_full == NULL)
        text_end_full = FindRenderedTextEnd(text);
    const ImVec2 text_size = text_size_if_known ? *text_size_if_known : CalcTextSize(text, text_end_full, false, 0.0f);

    //draw_list->AddLine(ImVec2(pos_max.x, pos_min.y - 4), ImVec2(pos_max.x, pos_max.y + 4), IM_COL32(0, 0, 255, 255));
    //draw_list->AddLine(ImVec2(ellipsis_max_x, pos_min.y-2), ImVec2(ellipsis_max_x, pos_max.y+2), IM_COL32(0, 255, 0, 255));
    //draw_list->AddLine(ImVec2(clip_max_x, pos_min.y), ImVec2(clip_max_x, pos_max.y), IM_COL32(255, 0, 0, 255));
    // FIXME: We could technically remove (last_glyph->AdvanceX - last_glyph->X1) from text_size.x here and save a few pixels.
    if (text_size.x > pos_max.x - pos_min.x)
    {
        // Hello wo...
        // |       |   |
        // min   max   ellipsis_max
        //          <-> this is generally some padding value

        const ImFont* font = draw_list->_Data->Font;
        const float font_size = draw_list->_Data->FontSize;
        const float font_scale = font_size / font->FontSize;
        const char* text_end_ellipsis = NULL;
        const float ellipsis_width = font->EllipsisWidth * font_scale;

        // We can now claim the space between pos_max.x and ellipsis_max.x
        const float text_avail_width = ImMax((ImMax(pos_max.x, ellipsis_max_x) - ellipsis_width) - pos_min.x, 1.0f);
        float text_size_clipped_x = font->CalcTextSizeA(font_size, text_avail_width, 0.0f, text, text_end_full, &text_end_ellipsis).x;
        if (text == text_end_ellipsis && text_end_ellipsis < text_end_full)
        {
            // Always display at least 1 character if there's no room for character + ellipsis
            text_end_ellipsis = text + ImTextCountUtf8BytesFromChar(text, text_end_full);
            text_size_clipped_x = font->CalcTextSizeA(font_size, FLT_MAX, 0.0f, text, text_end_ellipsis).x;
        }
        while (text_end_ellipsis > text && ImCharIsBlankA(text_end_ellipsis[-1]))
        {
            // Trim trailing space before ellipsis (FIXME: Supporting non-ascii blanks would be nice, for this we need a function to backtrack in UTF-8 text)
            text_end_ellipsis--;
            text_size_clipped_x -= font->CalcTextSizeA(font_size, FLT_MAX, 0.0f, text_end_ellipsis, text_end_ellipsis + 1).x; // Ascii blanks are always 1 byte
        }

        // Render text, render ellipsis
        RenderTextClippedEx(draw_list, pos_min, ImVec2(clip_max_x, pos_max.y), text, text_end_ellipsis, &text_size, ImVec2(0.0f, 0.0f));
        ImVec2 ellipsis_pos = ImTrunc(ImVec2(pos_min.x + text_size_clipped_x, pos_min.y));
        if (ellipsis_pos.x + ellipsis_width <= ellipsis_max_x)
            for (int i = 0; i < font->EllipsisCharCount; i++, ellipsis_pos.x += font->EllipsisCharStep * font_scale)
                font->RenderChar(draw_list, font_size, ellipsis_pos, GetColorU32(ImGuiCol_Text), font->EllipsisChar);
    }
    else
    {
        RenderTextClippedEx(draw_list, pos_min, ImVec2(clip_max_x, pos_max.y), text, text_end_full, &text_size, ImVec2(0.0f, 0.0f));
    }

    if (g.LogEnabled)
        LogRenderedText(&pos_min, text, text_end_full);
}

// Render a rectangle shaped with optional rounding and borders
void ImGui::RenderFrame(ImVec2 p_min, ImVec2 p_max, ImU32 fill_col, bool border, float rounding)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    window->DrawList->AddRectFilled(p_min, p_max, fill_col, rounding);
    const float border_size = g.Style.FrameBorderSize;
    if (border && border_size > 0.0f)
    {
        window->DrawList->AddRect(p_min + ImVec2(1, 1), p_max + ImVec2(1, 1), GetColorU32(ImGuiCol_BorderShadow), rounding, 0, border_size);
        window->DrawList->AddRect(p_min, p_max, GetColorU32(ImGuiCol_Border), rounding, 0, border_size);
    }
}

void ImGui::RenderFrameBorder(ImVec2 p_min, ImVec2 p_max, float rounding)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    const float border_size = g.Style.FrameBorderSize;
    if (border_size > 0.0f)
    {
        window->DrawList->AddRect(p_min + ImVec2(1, 1), p_max + ImVec2(1, 1), GetColorU32(ImGuiCol_BorderShadow), rounding, 0, border_size);
        window->DrawList->AddRect(p_min, p_max, GetColorU32(ImGuiCol_Border), rounding, 0, border_size);
    }
}

void ImGui::RenderNavHighlight(const ImRect& bb, ImGuiID id, ImGuiNavHighlightFlags flags)
{
    ImGuiContext& g = *GImGui;
    if (id != g.NavId)
        return;
    if (g.NavDisableHighlight && !(flags & ImGuiNavHighlightFlags_AlwaysDraw))
        return;
    ImGuiWindow* window = g.CurrentWindow;
    if (window->DC.NavHideHighlightOneFrame)
        return;

    float rounding = (flags & ImGuiNavHighlightFlags_NoRounding) ? 0.0f : g.Style.FrameRounding;
    ImRect display_rect = bb;
    display_rect.ClipWith(window->ClipRect);
    if (flags & ImGuiNavHighlightFlags_TypeDefault)
    {
        const float THICKNESS = 2.0f;
        const float DISTANCE = 3.0f + THICKNESS * 0.5f;
        display_rect.Expand(ImVec2(DISTANCE, DISTANCE));
        bool fully_visible = window->ClipRect.Contains(display_rect);
        if (!fully_visible)
            window->DrawList->PushClipRect(display_rect.Min, display_rect.Max);
        window->DrawList->AddRect(display_rect.Min + ImVec2(THICKNESS * 0.5f, THICKNESS * 0.5f), display_rect.Max - ImVec2(THICKNESS * 0.5f, THICKNESS * 0.5f), GetColorU32(ImGuiCol_NavHighlight), rounding, 0, THICKNESS);
        if (!fully_visible)
            window->DrawList->PopClipRect();
    }
    if (flags & ImGuiNavHighlightFlags_TypeThin)
    {
        window->DrawList->AddRect(display_rect.Min, display_rect.Max, GetColorU32(ImGuiCol_NavHighlight), rounding, 0, 1.0f);
    }
}

void ImGui::RenderMouseCursor(ImVec2 base_pos, float base_scale, ImGuiMouseCursor mouse_cursor, ImU32 col_fill, ImU32 col_border, ImU32 col_shadow)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(mouse_cursor > ImGuiMouseCursor_None && mouse_cursor < ImGuiMouseCursor_COUNT);
    ImFontAtlas* font_atlas = g.DrawListSharedData.Font->ContainerAtlas;
    for (ImGuiViewportP* viewport : g.Viewports)
    {
        // We scale cursor with current viewport/monitor, however Windows 10 for its own hardware cursor seems to be using a different scale factor.
        ImVec2 offset, size, uv[4];
        if (!font_atlas->GetMouseCursorTexData(mouse_cursor, &offset, &size, &uv[0], &uv[2]))
            continue;
        const ImVec2 pos = base_pos - offset;
        const float scale = base_scale * viewport->DpiScale;
        if (!viewport->GetMainRect().Overlaps(ImRect(pos, pos + ImVec2(size.x + 2, size.y + 2) * scale)))
            continue;
        ImDrawList* draw_list = GetForegroundDrawList(viewport);
        ImTextureID tex_id = font_atlas->TexID;
        draw_list->PushTextureID(tex_id);
        draw_list->AddImage(tex_id, pos + ImVec2(1, 0) * scale, pos + (ImVec2(1, 0) + size) * scale, uv[2], uv[3], col_shadow);
        draw_list->AddImage(tex_id, pos + ImVec2(2, 0) * scale, pos + (ImVec2(2, 0) + size) * scale, uv[2], uv[3], col_shadow);
        draw_list->AddImage(tex_id, pos,                        pos + size * scale,                  uv[2], uv[3], col_border);
        draw_list->AddImage(tex_id, pos,                        pos + size * scale,                  uv[0], uv[1], col_fill);
        draw_list->PopTextureID();
    }
}

//-----------------------------------------------------------------------------
// [SECTION] INITIALIZATION, SHUTDOWN
//-----------------------------------------------------------------------------

// Internal state access - if you want to share Dear ImGui state between modules (e.g. DLL) or allocate it yourself
// Note that we still point to some static data and members (such as GFontAtlas), so the state instance you end up using will point to the static data within its module
ImGuiContext* ImGui::GetCurrentContext()
{
    return GImGui;
}

void ImGui::SetCurrentContext(ImGuiContext* ctx)
{
#ifdef IMGUI_SET_CURRENT_CONTEXT_FUNC
    IMGUI_SET_CURRENT_CONTEXT_FUNC(ctx); // For custom thread-based hackery you may want to have control over this.
#else
    GImGui = ctx;
#endif
}

void ImGui::SetAllocatorFunctions(ImGuiMemAllocFunc alloc_func, ImGuiMemFreeFunc free_func, void* user_data)
{
    GImAllocatorAllocFunc = alloc_func;
    GImAllocatorFreeFunc = free_func;
    GImAllocatorUserData = user_data;
}

// This is provided to facilitate copying allocators from one static/DLL boundary to another (e.g. retrieve default allocator of your executable address space)
void ImGui::GetAllocatorFunctions(ImGuiMemAllocFunc* p_alloc_func, ImGuiMemFreeFunc* p_free_func, void** p_user_data)
{
    *p_alloc_func = GImAllocatorAllocFunc;
    *p_free_func = GImAllocatorFreeFunc;
    *p_user_data = GImAllocatorUserData;
}

ImGuiContext* ImGui::CreateContext(ImFontAtlas* shared_font_atlas)
{
    ImGuiContext* prev_ctx = GetCurrentContext();
    ImGuiContext* ctx = IM_NEW(ImGuiContext)(shared_font_atlas);
    SetCurrentContext(ctx);
    Initialize();
    if (prev_ctx != NULL)
        SetCurrentContext(prev_ctx); // Restore previous context if any, else keep new one.
    return ctx;
}

void ImGui::DestroyContext(ImGuiContext* ctx)
{
    ImGuiContext* prev_ctx = GetCurrentContext();
    if (ctx == NULL) //-V1051
        ctx = prev_ctx;
    SetCurrentContext(ctx);
    Shutdown();
    SetCurrentContext((prev_ctx != ctx) ? prev_ctx : NULL);
    IM_DELETE(ctx);
}

// IMPORTANT: ###xxx suffixes must be same in ALL languages
static const ImGuiLocEntry GLocalizationEntriesEnUS[] =
{
    { ImGuiLocKey_VersionStr,           "Dear ImGui " IMGUI_VERSION " (" IM_STRINGIFY(IMGUI_VERSION_NUM) ")" },
    { ImGuiLocKey_TableSizeOne,         "Size column to fit###SizeOne"          },
    { ImGuiLocKey_TableSizeAllFit,      "Size all columns to fit###SizeAll"     },
    { ImGuiLocKey_TableSizeAllDefault,  "Size all columns to default###SizeAll" },
    { ImGuiLocKey_TableResetOrder,      "Reset order###ResetOrder"              },
    { ImGuiLocKey_WindowingMainMenuBar, "(Main menu bar)"                       },
    { ImGuiLocKey_WindowingPopup,       "(Popup)"                               },
    { ImGuiLocKey_WindowingUntitled,    "(Untitled)"                            },
    { ImGuiLocKey_DockingHideTabBar,    "Hide tab bar###HideTabBar"             },
    { ImGuiLocKey_DockingHoldShiftToDock,       "Hold SHIFT to enable Docking window."  },
    { ImGuiLocKey_DockingDragToUndockOrMoveNode,"Click and drag to move or undock whole node."    },
};

void ImGui::Initialize()
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(!g.Initialized && !g.SettingsLoaded);

    // Add .ini handle for ImGuiWindow and ImGuiTable types
    {
        ImGuiSettingsHandler ini_handler;
        ini_handler.TypeName = "Window";
        ini_handler.TypeHash = ImHashStr("Window");
        ini_handler.ClearAllFn = WindowSettingsHandler_ClearAll;
        ini_handler.ReadOpenFn = WindowSettingsHandler_ReadOpen;
        ini_handler.ReadLineFn = WindowSettingsHandler_ReadLine;
        ini_handler.ApplyAllFn = WindowSettingsHandler_ApplyAll;
        ini_handler.WriteAllFn = WindowSettingsHandler_WriteAll;
        AddSettingsHandler(&ini_handler);
    }
    TableSettingsAddSettingsHandler();

    // Setup default localization table
    LocalizeRegisterEntries(GLocalizationEntriesEnUS, IM_ARRAYSIZE(GLocalizationEntriesEnUS));

    // Setup default platform clipboard/IME handlers.
    g.IO.GetClipboardTextFn = GetClipboardTextFn_DefaultImpl;    // Platform dependent default implementations
    g.IO.SetClipboardTextFn = SetClipboardTextFn_DefaultImpl;
    g.IO.ClipboardUserData = (void*)&g;                          // Default implementation use the ImGuiContext as user data (ideally those would be arguments to the function)
    g.IO.SetPlatformImeDataFn = SetPlatformImeDataFn_DefaultImpl;

    // Create default viewport
    ImGuiViewportP* viewport = IM_NEW(ImGuiViewportP)();
    viewport->ID = IMGUI_VIEWPORT_DEFAULT_ID;
    viewport->Idx = 0;
    viewport->PlatformWindowCreated = true;
    viewport->Flags = ImGuiViewportFlags_OwnedByApp;
    g.Viewports.push_back(viewport);
    g.TempBuffer.resize(1024 * 3 + 1, 0);
    g.ViewportCreatedCount++;
    g.PlatformIO.Viewports.push_back(g.Viewports[0]);

#ifdef IMGUI_HAS_DOCK
    // Initialize Docking
    DockContextInitialize(&g);
#endif

    g.Initialized = true;
}

// This function is merely here to free heap allocations.
void ImGui::Shutdown()
{
    // The fonts atlas can be used prior to calling NewFrame(), so we clear it even if g.Initialized is FALSE (which would happen if we never called NewFrame)
    ImGuiContext& g = *GImGui;
    if (g.IO.Fonts && g.FontAtlasOwnedByContext)
    {
        g.IO.Fonts->Locked = false;
        IM_DELETE(g.IO.Fonts);
    }
    g.IO.Fonts = NULL;
    g.DrawListSharedData.TempBuffer.clear();

    // Cleanup of other data are conditional on actually having initialized Dear ImGui.
    if (!g.Initialized)
        return;

    // Save settings (unless we haven't attempted to load them: CreateContext/DestroyContext without a call to NewFrame shouldn't save an empty file)
    if (g.SettingsLoaded && g.IO.IniFilename != NULL)
        SaveIniSettingsToDisk(g.IO.IniFilename);

    // Destroy platform windows
    DestroyPlatformWindows();

    // Shutdown extensions
    DockContextShutdown(&g);

    CallContextHooks(&g, ImGuiContextHookType_Shutdown);

    // Clear everything else
    g.Windows.clear_delete();
    g.WindowsFocusOrder.clear();
    g.WindowsTempSortBuffer.clear();
    g.CurrentWindow = NULL;
    g.CurrentWindowStack.clear();
    g.WindowsById.Clear();
    g.NavWindow = NULL;
    g.HoveredWindow = g.HoveredWindowUnderMovingWindow = NULL;
    g.ActiveIdWindow = g.ActiveIdPreviousFrameWindow = NULL;
    g.MovingWindow = NULL;

    g.KeysRoutingTable.Clear();

    g.ColorStack.clear();
    g.StyleVarStack.clear();
    g.FontStack.clear();
    g.OpenPopupStack.clear();
    g.BeginPopupStack.clear();
    g.NavTreeNodeStack.clear();

    g.CurrentViewport = g.MouseViewport = g.MouseLastHoveredViewport = NULL;
    g.Viewports.clear_delete();

    g.TabBars.Clear();
    g.CurrentTabBarStack.clear();
    g.ShrinkWidthBuffer.clear();

    g.ClipperTempData.clear_destruct();

    g.Tables.Clear();
    g.TablesTempData.clear_destruct();
    g.DrawChannelsTempMergeBuffer.clear();

    g.ClipboardHandlerData.clear();
    g.MenusIdSubmittedThisFrame.clear();
    g.InputTextState.ClearFreeMemory();
    g.InputTextDeactivatedState.ClearFreeMemory();

    g.SettingsWindows.clear();
    g.SettingsHandlers.clear();

    if (g.LogFile)
    {
#ifndef IMGUI_DISABLE_TTY_FUNCTIONS
        if (g.LogFile != stdout)
#endif
            ImFileClose(g.LogFile);
        g.LogFile = NULL;
    }
    g.LogBuffer.clear();
    g.DebugLogBuf.clear();
    g.DebugLogIndex.clear();

    g.Initialized = false;
}

// No specific ordering/dependency support, will see as needed
ImGuiID ImGui::AddContextHook(ImGuiContext* ctx, const ImGuiContextHook* hook)
{
    ImGuiContext& g = *ctx;
    IM_ASSERT(hook->Callback != NULL && hook->HookId == 0 && hook->Type != ImGuiContextHookType_PendingRemoval_);
    g.Hooks.push_back(*hook);
    g.Hooks.back().HookId = ++g.HookIdNext;
    return g.HookIdNext;
}

// Deferred removal, avoiding issue with changing vector while iterating it
void ImGui::RemoveContextHook(ImGuiContext* ctx, ImGuiID hook_id)
{
    ImGuiContext& g = *ctx;
    IM_ASSERT(hook_id != 0);
    for (ImGuiContextHook& hook : g.Hooks)
        if (hook.HookId == hook_id)
            hook.Type = ImGuiContextHookType_PendingRemoval_;
}

// Call context hooks (used by e.g. test engine)
// We assume a small number of hooks so all stored in same array
void ImGui::CallContextHooks(ImGuiContext* ctx, ImGuiContextHookType hook_type)
{
    ImGuiContext& g = *ctx;
    for (ImGuiContextHook& hook : g.Hooks)
        if (hook.Type == hook_type)
            hook.Callback(&g, &hook);
}


//-----------------------------------------------------------------------------
// [SECTION] MAIN CODE (most of the code! lots of stuff, needs tidying up!)
//-----------------------------------------------------------------------------

// ImGuiWindow is mostly a dumb struct. It merely has a constructor and a few helper methods
ImGuiWindow::ImGuiWindow(ImGuiContext* ctx, const char* name) : DrawListInst(NULL)
{
    memset(this, 0, sizeof(*this));
    Ctx = ctx;
    Name = ImStrdup(name);
    NameBufLen = (int)strlen(name) + 1;
    ID = ImHashStr(name);
    IDStack.push_back(ID);
    ViewportAllowPlatformMonitorExtend = -1;
    ViewportPos = ImVec2(FLT_MAX, FLT_MAX);
    MoveId = GetID("#MOVE");
    TabId = GetID("#TAB");
    ScrollTarget = ImVec2(FLT_MAX, FLT_MAX);
    ScrollTargetCenterRatio = ImVec2(0.5f, 0.5f);
    AutoFitFramesX = AutoFitFramesY = -1;
    AutoPosLastDirection = ImGuiDir_None;
    SetWindowPosAllowFlags = SetWindowSizeAllowFlags = SetWindowCollapsedAllowFlags = SetWindowDockAllowFlags = 0;
    SetWindowPosVal = SetWindowPosPivot = ImVec2(FLT_MAX, FLT_MAX);
    LastFrameActive = -1;
    LastFrameJustFocused = -1;
    LastTimeActive = -1.0f;
    FontWindowScale = FontDpiScale = 1.0f;
    SettingsOffset = -1;
    DockOrder = -1;
    DrawList = &DrawListInst;
    DrawList->_Data = &Ctx->DrawListSharedData;
    DrawList->_OwnerName = Name;
    NavPreferredScoringPosRel[0] = NavPreferredScoringPosRel[1] = ImVec2(FLT_MAX, FLT_MAX);
    IM_PLACEMENT_NEW(&WindowClass) ImGuiWindowClass();
}

ImGuiWindow::~ImGuiWindow()
{
    IM_ASSERT(DrawList == &DrawListInst);
    IM_DELETE(Name);
    ColumnsStorage.clear_destruct();
}

ImGuiID ImGuiWindow::GetID(const char* str, const char* str_end)
{
    ImGuiID seed = IDStack.back();
    ImGuiID id = ImHashStr(str, str_end ? (str_end - str) : 0, seed);
    ImGuiContext& g = *Ctx;
    if (g.DebugHookIdInfo == id)
        ImGui::DebugHookIdInfo(id, ImGuiDataType_String, str, str_end);
    return id;
}

ImGuiID ImGuiWindow::GetID(const void* ptr)
{
    ImGuiID seed = IDStack.back();
    ImGuiID id = ImHashData(&ptr, sizeof(void*), seed);
    ImGuiContext& g = *Ctx;
    if (g.DebugHookIdInfo == id)
        ImGui::DebugHookIdInfo(id, ImGuiDataType_Pointer, ptr, NULL);
    return id;
}

ImGuiID ImGuiWindow::GetID(int n)
{
    ImGuiID seed = IDStack.back();
    ImGuiID id = ImHashData(&n, sizeof(n), seed);
    ImGuiContext& g = *Ctx;
    if (g.DebugHookIdInfo == id)
        ImGui::DebugHookIdInfo(id, ImGuiDataType_S32, (void*)(intptr_t)n, NULL);
    return id;
}

// This is only used in rare/specific situations to manufacture an ID out of nowhere.
ImGuiID ImGuiWindow::GetIDFromRectangle(const ImRect& r_abs)
{
    ImGuiID seed = IDStack.back();
    ImRect r_rel = ImGui::WindowRectAbsToRel(this, r_abs);
    ImGuiID id = ImHashData(&r_rel, sizeof(r_rel), seed);
    return id;
}

static void SetCurrentWindow(ImGuiWindow* window)
{
    ImGuiContext& g = *GImGui;
    g.CurrentWindow = window;
    g.CurrentTable = window && window->DC.CurrentTableIdx != -1 ? g.Tables.GetByIndex(window->DC.CurrentTableIdx) : NULL;
    if (window)
    {
        g.FontSize = g.DrawListSharedData.FontSize = window->CalcFontSize();
        ImGui::NavUpdateCurrentWindowIsScrollPushableX();
    }
}

void ImGui::GcCompactTransientMiscBuffers()
{
    ImGuiContext& g = *GImGui;
    g.ItemFlagsStack.clear();
    g.GroupStack.clear();
    TableGcCompactSettings();
}

// Free up/compact internal window buffers, we can use this when a window becomes unused.
// Not freed:
// - ImGuiWindow, ImGuiWindowSettings, Name, StateStorage, ColumnsStorage (may hold useful data)
// This should have no noticeable visual effect. When the window reappear however, expect new allocation/buffer growth/copy cost.
void ImGui::GcCompactTransientWindowBuffers(ImGuiWindow* window)
{
    window->MemoryCompacted = true;
    window->MemoryDrawListIdxCapacity = window->DrawList->IdxBuffer.Capacity;
    window->MemoryDrawListVtxCapacity = window->DrawList->VtxBuffer.Capacity;
    window->IDStack.clear();
    window->DrawList->_ClearFreeMemory();
    window->DC.ChildWindows.clear();
    window->DC.ItemWidthStack.clear();
    window->DC.TextWrapPosStack.clear();
}

void ImGui::GcAwakeTransientWindowBuffers(ImGuiWindow* window)
{
    // We stored capacity of the ImDrawList buffer to reduce growth-caused allocation/copy when awakening.
    // The other buffers tends to amortize much faster.
    window->MemoryCompacted = false;
    window->DrawList->IdxBuffer.reserve(window->MemoryDrawListIdxCapacity);
    window->DrawList->VtxBuffer.reserve(window->MemoryDrawListVtxCapacity);
    window->MemoryDrawListIdxCapacity = window->MemoryDrawListVtxCapacity = 0;
}

void ImGui::SetActiveID(ImGuiID id, ImGuiWindow* window)
{
    ImGuiContext& g = *GImGui;

    // Clear previous active id
    if (g.ActiveId != 0)
    {
        // While most behaved code would make an effort to not steal active id during window move/drag operations,
        // we at least need to be resilient to it. Canceling the move is rather aggressive and users of 'master' branch
        // may prefer the weird ill-defined half working situation ('docking' did assert), so may need to rework that.
        if (g.MovingWindow != NULL && g.ActiveId == g.MovingWindow->MoveId)
        {
            IMGUI_DEBUG_LOG_ACTIVEID("SetActiveID() cancel MovingWindow\n");
            g.MovingWindow = NULL;
        }

        // This could be written in a more general way (e.g associate a hook to ActiveId),
        // but since this is currently quite an exception we'll leave it as is.
        // One common scenario leading to this is: pressing Key ->NavMoveRequestApplyResult() -> ClearActiveId()
        if (g.InputTextState.ID == g.ActiveId)
            InputTextDeactivateHook(g.ActiveId);
    }

    // Set active id
    g.ActiveIdIsJustActivated = (g.ActiveId != id);
    if (g.ActiveIdIsJustActivated)
    {
        IMGUI_DEBUG_LOG_ACTIVEID("SetActiveID() old:0x%08X (window \"%s\") -> new:0x%08X (window \"%s\")\n", g.ActiveId, g.ActiveIdWindow ? g.ActiveIdWindow->Name : "", id, window ? window->Name : "");
        g.ActiveIdTimer = 0.0f;
        g.ActiveIdHasBeenPressedBefore = false;
        g.ActiveIdHasBeenEditedBefore = false;
        g.ActiveIdMouseButton = -1;
        if (id != 0)
        {
            g.LastActiveId = id;
            g.LastActiveIdTimer = 0.0f;
        }
    }
    g.ActiveId = id;
    g.ActiveIdAllowOverlap = false;
    g.ActiveIdNoClearOnFocusLoss = false;
    g.ActiveIdWindow = window;
    g.ActiveIdHasBeenEditedThisFrame = false;
    if (id)
    {
        g.ActiveIdIsAlive = id;
        g.ActiveIdSource = (g.NavActivateId == id || g.NavJustMovedToId == id) ? g.NavInputSource : ImGuiInputSource_Mouse;
        IM_ASSERT(g.ActiveIdSource != ImGuiInputSource_None);
    }

    // Clear declaration of inputs claimed by the widget
    // (Please note that this is WIP and not all keys/inputs are thoroughly declared by all widgets yet)
    g.ActiveIdUsingNavDirMask = 0x00;
    g.ActiveIdUsingAllKeyboardKeys = false;
#ifndef IMGUI_DISABLE_OBSOLETE_KEYIO
    g.ActiveIdUsingNavInputMask = 0x00;
#endif
}

void ImGui::ClearActiveID()
{
    SetActiveID(0, NULL); // g.ActiveId = 0;
}

void ImGui::SetHoveredID(ImGuiID id)
{
    ImGuiContext& g = *GImGui;
    g.HoveredId = id;
    g.HoveredIdAllowOverlap = false;
    if (id != 0 && g.HoveredIdPreviousFrame != id)
        g.HoveredIdTimer = g.HoveredIdNotActiveTimer = 0.0f;
}

ImGuiID ImGui::GetHoveredID()
{
    ImGuiContext& g = *GImGui;
    return g.HoveredId ? g.HoveredId : g.HoveredIdPreviousFrame;
}

// This is called by ItemAdd().
// Code not using ItemAdd() may need to call this manually otherwise ActiveId will be cleared. In IMGUI_VERSION_NUM < 18717 this was called by GetID().
void ImGui::KeepAliveID(ImGuiID id)
{
    ImGuiContext& g = *GImGui;
    if (g.ActiveId == id)
        g.ActiveIdIsAlive = id;
    if (g.ActiveIdPreviousFrame == id)
        g.ActiveIdPreviousFrameIsAlive = true;
}

void ImGui::MarkItemEdited(ImGuiID id)
{
    // This marking is solely to be able to provide info for IsItemDeactivatedAfterEdit().
    // ActiveId might have been released by the time we call this (as in the typical press/release button behavior) but still need to fill the data.
    ImGuiContext& g = *GImGui;
    if (g.LockMarkEdited > 0)
        return;
    if (g.ActiveId == id || g.ActiveId == 0)
    {
        g.ActiveIdHasBeenEditedThisFrame = true;
        g.ActiveIdHasBeenEditedBefore = true;
    }

    // We accept a MarkItemEdited() on drag and drop targets (see https://github.com/ocornut/imgui/issues/1875#issuecomment-978243343)
    // We accept 'ActiveIdPreviousFrame == id' for InputText() returning an edit after it has been taken ActiveId away (#4714)
    IM_ASSERT(g.DragDropActive || g.ActiveId == id || g.ActiveId == 0 || g.ActiveIdPreviousFrame == id);

    //IM_ASSERT(g.CurrentWindow->DC.LastItemId == id);
    g.LastItemData.StatusFlags |= ImGuiItemStatusFlags_Edited;
}

bool ImGui::IsWindowContentHoverable(ImGuiWindow* window, ImGuiHoveredFlags flags)
{
    // An active popup disable hovering on other windows (apart from its own children)
    // FIXME-OPT: This could be cached/stored within the window.
    ImGuiContext& g = *GImGui;
    if (g.NavWindow)
        if (ImGuiWindow* focused_root_window = g.NavWindow->RootWindowDockTree)
            if (focused_root_window->WasActive && focused_root_window != window->RootWindowDockTree)
            {
                // For the purpose of those flags we differentiate "standard popup" from "modal popup"
                // NB: The 'else' is important because Modal windows are also Popups.
                bool want_inhibit = false;
                if (focused_root_window->Flags & ImGuiWindowFlags_Modal)
                    want_inhibit = true;
                else if ((focused_root_window->Flags & ImGuiWindowFlags_Popup) && !(flags & ImGuiHoveredFlags_AllowWhenBlockedByPopup))
                    want_inhibit = true;

                // Inhibit hover unless the window is within the stack of our modal/popup
                if (want_inhibit)
                    if (!IsWindowWithinBeginStackOf(window->RootWindow, focused_root_window))
                        return false;
            }

    // Filter by viewport
    if (window->Viewport != g.MouseViewport)
        if (g.MovingWindow == NULL || window->RootWindowDockTree != g.MovingWindow->RootWindowDockTree)
            return false;

    return true;
}

static inline float CalcDelayFromHoveredFlags(ImGuiHoveredFlags flags)
{
    ImGuiContext& g = *GImGui;
    if (flags & ImGuiHoveredFlags_DelayNormal)
        return g.Style.HoverDelayNormal;
    if (flags & ImGuiHoveredFlags_DelayShort)
        return g.Style.HoverDelayShort;
    return 0.0f;
}

static ImGuiHoveredFlags ApplyHoverFlagsForTooltip(ImGuiHoveredFlags user_flags, ImGuiHoveredFlags shared_flags)
{
    // Allow instance flags to override shared flags
    if (user_flags & (ImGuiHoveredFlags_DelayNone | ImGuiHoveredFlags_DelayShort | ImGuiHoveredFlags_DelayNormal))
        shared_flags &= ~(ImGuiHoveredFlags_DelayNone | ImGuiHoveredFlags_DelayShort | ImGuiHoveredFlags_DelayNormal);
    return user_flags | shared_flags;
}

// This is roughly matching the behavior of internal-facing ItemHoverable()
// - we allow hovering to be true when ActiveId==window->MoveID, so that clicking on non-interactive items such as a Text() item still returns true with IsItemHovered()
// - this should work even for non-interactive items that have no ID, so we cannot use LastItemId
bool ImGui::IsItemHovered(ImGuiHoveredFlags flags)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    IM_ASSERT((flags & ~ImGuiHoveredFlags_AllowedMaskForIsItemHovered) == 0 && "Invalid flags for IsItemHovered()!");

    if (g.NavDisableMouseHover && !g.NavDisableHighlight && !(flags & ImGuiHoveredFlags_NoNavOverride))
    {
        if ((g.LastItemData.InFlags & ImGuiItemFlags_Disabled) && !(flags & ImGuiHoveredFlags_AllowWhenDisabled))
            return false;
        if (!IsItemFocused())
            return false;

        if (flags & ImGuiHoveredFlags_ForTooltip)
            flags = ApplyHoverFlagsForTooltip(flags, g.Style.HoverFlagsForTooltipNav);
    }
    else
    {
        // Test for bounding box overlap, as updated as ItemAdd()
        ImGuiItemStatusFlags status_flags = g.LastItemData.StatusFlags;
        if (!(status_flags & ImGuiItemStatusFlags_HoveredRect))
            return false;

        if (flags & ImGuiHoveredFlags_ForTooltip)
            flags = ApplyHoverFlagsForTooltip(flags, g.Style.HoverFlagsForTooltipMouse);

        IM_ASSERT((flags & (ImGuiHoveredFlags_AnyWindow | ImGuiHoveredFlags_RootWindow | ImGuiHoveredFlags_ChildWindows | ImGuiHoveredFlags_NoPopupHierarchy | ImGuiHoveredFlags_DockHierarchy)) == 0);   // Flags not supported by this function

        // Done with rectangle culling so we can perform heavier checks now
        // Test if we are hovering the right window (our window could be behind another window)
        // [2021/03/02] Reworked / reverted the revert, finally. Note we want e.g. BeginGroup/ItemAdd/EndGroup to work as well. (#3851)
        // [2017/10/16] Reverted commit 344d48be3 and testing RootWindow instead. I believe it is correct to NOT test for RootWindow but this leaves us unable
        // to use IsItemHovered() after EndChild() itself. Until a solution is found I believe reverting to the test from 2017/09/27 is safe since this was
        // the test that has been running for a long while.
        if (g.HoveredWindow != window && (status_flags & ImGuiItemStatusFlags_HoveredWindow) == 0)
            if ((flags & ImGuiHoveredFlags_AllowWhenOverlappedByWindow) == 0)
                return false;

        // Test if another item is active (e.g. being dragged)
        const ImGuiID id = g.LastItemData.ID;
        if ((flags & ImGuiHoveredFlags_AllowWhenBlockedByActiveItem) == 0)
            if (g.ActiveId != 0 && g.ActiveId != id && !g.ActiveIdAllowOverlap)
                if (g.ActiveId != window->MoveId && g.ActiveId != window->TabId)
                    return false;

        // Test if interactions on this window are blocked by an active popup or modal.
        // The ImGuiHoveredFlags_AllowWhenBlockedByPopup flag will be tested here.
        if (!IsWindowContentHoverable(window, flags) && !(g.LastItemData.InFlags & ImGuiItemFlags_NoWindowHoverableCheck))
            return false;

        // Test if the item is disabled
        if ((g.LastItemData.InFlags & ImGuiItemFlags_Disabled) && !(flags & ImGuiHoveredFlags_AllowWhenDisabled))
            return false;

        // Special handling for calling after Begin() which represent the title bar or tab.
        // When the window is skipped/collapsed (SkipItems==true) that last item (always ->MoveId submitted by Begin)
        // will never be overwritten so we need to detect the case.
        if (id == window->MoveId && window->WriteAccessed)
            return false;

        // Test if using AllowOverlap and overlapped
        if ((g.LastItemData.InFlags & ImGuiItemFlags_AllowOverlap) && id != 0)
            if ((flags & ImGuiHoveredFlags_AllowWhenOverlappedByItem) == 0)
                if (g.HoveredIdPreviousFrame != g.LastItemData.ID)
                    return false;
    }

    // Handle hover delay
    // (some ideas: https://www.nngroup.com/articles/timing-exposing-content)
    const float delay = CalcDelayFromHoveredFlags(flags);
    if (delay > 0.0f || (flags & ImGuiHoveredFlags_Stationary))
    {
        ImGuiID hover_delay_id = (g.LastItemData.ID != 0) ? g.LastItemData.ID : window->GetIDFromRectangle(g.LastItemData.Rect);
        if ((flags & ImGuiHoveredFlags_NoSharedDelay) && (g.HoverItemDelayIdPreviousFrame != hover_delay_id))
            g.HoverItemDelayTimer = 0.0f;
        g.HoverItemDelayId = hover_delay_id;

        // When changing hovered item we requires a bit of stationary delay before activating hover timer,
        // but once unlocked on a given item we also moving.
        //if (g.HoverDelayTimer >= delay && (g.HoverDelayTimer - g.IO.DeltaTime < delay || g.MouseStationaryTimer - g.IO.DeltaTime < g.Style.HoverStationaryDelay)) { IMGUI_DEBUG_LOG("HoverDelayTimer = %f/%f, MouseStationaryTimer = %f\n", g.HoverDelayTimer, delay, g.MouseStationaryTimer); }
        if ((flags & ImGuiHoveredFlags_Stationary) != 0 && g.HoverItemUnlockedStationaryId != hover_delay_id)
            return false;

        if (g.HoverItemDelayTimer < delay)
            return false;
    }

    return true;
}

// Internal facing ItemHoverable() used when submitting widgets. Differs slightly from IsItemHovered().
// (this does not rely on LastItemData it can be called from a ButtonBehavior() call not following an ItemAdd() call)
// FIXME-LEGACY: the 'ImGuiItemFlags item_flags' parameter was added on 2023-06-28.
// If you used this in your legacy/custom widgets code:
// - Commonly: if your ItemHoverable() call comes after an ItemAdd() call: pass 'item_flags = g.LastItemData.InFlags'.
// - Rare: otherwise you may pass 'item_flags = 0' (ImGuiItemFlags_None) unless you want to benefit from special behavior handled by ItemHoverable.
bool ImGui::ItemHoverable(const ImRect& bb, ImGuiID id, ImGuiItemFlags item_flags)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    if (g.HoveredWindow != window)
        return false;
    if (!IsMouseHoveringRect(bb.Min, bb.Max))
        return false;

    if (g.HoveredId != 0 && g.HoveredId != id && !g.HoveredIdAllowOverlap)
        return false;
    if (g.ActiveId != 0 && g.ActiveId != id && !g.ActiveIdAllowOverlap)
        return false;

    // Done with rectangle culling so we can perform heavier checks now.
    if (!(item_flags & ImGuiItemFlags_NoWindowHoverableCheck) && !IsWindowContentHoverable(window, ImGuiHoveredFlags_None))
    {
        g.HoveredIdDisabled = true;
        return false;
    }

    // We exceptionally allow this function to be called with id==0 to allow using it for easy high-level
    // hover test in widgets code. We could also decide to split this function is two.
    if (id != 0)
    {
        // Drag source doesn't report as hovered
        if (g.DragDropActive && g.DragDropPayload.SourceId == id && !(g.DragDropSourceFlags & ImGuiDragDropFlags_SourceNoDisableHover))
            return false;

        SetHoveredID(id);

        // AllowOverlap mode (rarely used) requires previous frame HoveredId to be null or to match.
        // This allows using patterns where a later submitted widget overlaps a previous one. Generally perceived as a front-to-back hit-test.
        if (item_flags & ImGuiItemFlags_AllowOverlap)
        {
            g.HoveredIdAllowOverlap = true;
            if (g.HoveredIdPreviousFrame != id)
                return false;
        }
    }

    // When disabled we'll return false but still set HoveredId
    if (item_flags & ImGuiItemFlags_Disabled)
    {
        // Release active id if turning disabled
        if (g.ActiveId == id && id != 0)
            ClearActiveID();
        g.HoveredIdDisabled = true;
        return false;
    }

    if (id != 0)
    {
        // [DEBUG] Item Picker tool!
        // We perform the check here because SetHoveredID() is not frequently called (1~ time a frame), making
        // the cost of this tool near-zero. We can get slightly better call-stack and support picking non-hovered
        // items if we performed the test in ItemAdd(), but that would incur a small runtime cost.
        if (g.DebugItemPickerActive && g.HoveredIdPreviousFrame == id)
            GetForegroundDrawList()->AddRect(bb.Min, bb.Max, IM_COL32(255, 255, 0, 255));
        if (g.DebugItemPickerBreakId == id)
            IM_DEBUG_BREAK();
    }

    if (g.NavDisableMouseHover)
        return false;

    return true;
}

// FIXME: This is inlined/duplicated in ItemAdd()
bool ImGui::IsClippedEx(const ImRect& bb, ImGuiID id)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    if (!bb.Overlaps(window->ClipRect))
        if (id == 0 || (id != g.ActiveId && id != g.NavId))
            if (!g.LogEnabled)
                return true;
    return false;
}

// This is also inlined in ItemAdd()
// Note: if ImGuiItemStatusFlags_HasDisplayRect is set, user needs to set g.LastItemData.DisplayRect.
void ImGui::SetLastItemData(ImGuiID item_id, ImGuiItemFlags in_flags, ImGuiItemStatusFlags item_flags, const ImRect& item_rect)
{
    ImGuiContext& g = *GImGui;
    g.LastItemData.ID = item_id;
    g.LastItemData.InFlags = in_flags;
    g.LastItemData.StatusFlags = item_flags;
    g.LastItemData.Rect = g.LastItemData.NavRect = item_rect;
}

float ImGui::CalcWrapWidthForPos(const ImVec2& pos, float wrap_pos_x)
{
    if (wrap_pos_x < 0.0f)
        return 0.0f;

    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    if (wrap_pos_x == 0.0f)
    {
        // We could decide to setup a default wrapping max point for auto-resizing windows,
        // or have auto-wrap (with unspecified wrapping pos) behave as a ContentSize extending function?
        //if (window->Hidden && (window->Flags & ImGuiWindowFlags_AlwaysAutoResize))
        //    wrap_pos_x = ImMax(window->WorkRect.Min.x + g.FontSize * 10.0f, window->WorkRect.Max.x);
        //else
        wrap_pos_x = window->WorkRect.Max.x;
    }
    else if (wrap_pos_x > 0.0f)
    {
        wrap_pos_x += window->Pos.x - window->Scroll.x; // wrap_pos_x is provided is window local space
    }

    return ImMax(wrap_pos_x - pos.x, 1.0f);
}

// IM_ALLOC() == ImGui::MemAlloc()
void* ImGui::MemAlloc(size_t size)
{
    void* ptr = (*GImAllocatorAllocFunc)(size, GImAllocatorUserData);
#ifndef IMGUI_DISABLE_DEBUG_TOOLS
    if (ImGuiContext* ctx = GImGui)
        DebugAllocHook(&ctx->DebugAllocInfo, ctx->FrameCount, ptr, size);
#endif
    return ptr;
}

// IM_FREE() == ImGui::MemFree()
void ImGui::MemFree(void* ptr)
{
#ifndef IMGUI_DISABLE_DEBUG_TOOLS
    if (ptr != NULL)
        if (ImGuiContext* ctx = GImGui)
            DebugAllocHook(&ctx->DebugAllocInfo, ctx->FrameCount, ptr, (size_t)-1);
#endif
    return (*GImAllocatorFreeFunc)(ptr, GImAllocatorUserData);
}

// We record the number of allocation in recent frames, as a way to audit/sanitize our guiding principles of "no allocations on idle/repeating frames"
void ImGui::DebugAllocHook(ImGuiDebugAllocInfo* info, int frame_count, void* ptr, size_t size)
{
    ImGuiDebugAllocEntry* entry = &info->LastEntriesBuf[info->LastEntriesIdx];
    IM_UNUSED(ptr);
    if (entry->FrameCount != frame_count)
    {
        info->LastEntriesIdx = (info->LastEntriesIdx + 1) % IM_ARRAYSIZE(info->LastEntriesBuf);
        entry = &info->LastEntriesBuf[info->LastEntriesIdx];
        entry->FrameCount = frame_count;
        entry->AllocCount = entry->FreeCount = 0;
    }
    if (size != (size_t)-1)
    {
        entry->AllocCount++;
        info->TotalAllocCount++;
        //printf("[%05d] MemAlloc(%d) -> 0x%p\n", frame_count, size, ptr);
    }
    else
    {
        entry->FreeCount++;
        info->TotalFreeCount++;
        //printf("[%05d] MemFree(0x%p)\n", frame_count, ptr);
    }
}

const char* ImGui::GetClipboardText()
{
    ImGuiContext& g = *GImGui;
    return g.IO.GetClipboardTextFn ? g.IO.GetClipboardTextFn(g.IO.ClipboardUserData) : "";
}

void ImGui::SetClipboardText(const char* text)
{
    ImGuiContext& g = *GImGui;
    if (g.IO.SetClipboardTextFn)
        g.IO.SetClipboardTextFn(g.IO.ClipboardUserData, text);
}

const char* ImGui::GetVersion()
{
    return IMGUI_VERSION;
}

ImGuiIO& ImGui::GetIO()
{
    IM_ASSERT(GImGui != NULL && "No current context. Did you call ImGui::CreateContext() and ImGui::SetCurrentContext() ?");
    return GImGui->IO;
}

ImGuiPlatformIO& ImGui::GetPlatformIO()
{
    IM_ASSERT(GImGui != NULL && "No current context. Did you call ImGui::CreateContext() or ImGui::SetCurrentContext()?");
    return GImGui->PlatformIO;
}

// Pass this to your backend rendering function! Valid after Render() and until the next call to NewFrame()
ImDrawData* ImGui::GetDrawData()
{
    ImGuiContext& g = *GImGui;
    ImGuiViewportP* viewport = g.Viewports[0];
    return viewport->DrawDataP.Valid ? &viewport->DrawDataP : NULL;
}

double ImGui::GetTime()
{
    return GImGui->Time;
}

int ImGui::GetFrameCount()
{
    return GImGui->FrameCount;
}

static ImDrawList* GetViewportBgFgDrawList(ImGuiViewportP* viewport, size_t drawlist_no, const char* drawlist_name)
{
    // Create the draw list on demand, because they are not frequently used for all viewports
    ImGuiContext& g = *GImGui;
    IM_ASSERT(drawlist_no < IM_ARRAYSIZE(viewport->BgFgDrawLists));
    ImDrawList* draw_list = viewport->BgFgDrawLists[drawlist_no];
    if (draw_list == NULL)
    {
        draw_list = IM_NEW(ImDrawList)(&g.DrawListSharedData);
        draw_list->_OwnerName = drawlist_name;
        viewport->BgFgDrawLists[drawlist_no] = draw_list;
    }

    // Our ImDrawList system requires that there is always a command
    if (viewport->BgFgDrawListsLastFrame[drawlist_no] != g.FrameCount)
    {
        draw_list->_ResetForNewFrame();
        draw_list->PushTextureID(g.IO.Fonts->TexID);
        draw_list->PushClipRect(viewport->Pos, viewport->Pos + viewport->Size, false);
        viewport->BgFgDrawListsLastFrame[drawlist_no] = g.FrameCount;
    }
    return draw_list;
}

ImDrawList* ImGui::GetBackgroundDrawList(ImGuiViewport* viewport)
{
    return GetViewportBgFgDrawList((ImGuiViewportP*)viewport, 0, "##Background");
}

ImDrawList* ImGui::GetBackgroundDrawList()
{
    ImGuiContext& g = *GImGui;
    return GetBackgroundDrawList(g.CurrentWindow->Viewport);
}

ImDrawList* ImGui::GetForegroundDrawList(ImGuiViewport* viewport)
{
    return GetViewportBgFgDrawList((ImGuiViewportP*)viewport, 1, "##Foreground");
}

ImDrawList* ImGui::GetForegroundDrawList()
{
    ImGuiContext& g = *GImGui;
    return GetForegroundDrawList(g.CurrentWindow->Viewport);
}

ImDrawListSharedData* ImGui::GetDrawListSharedData()
{
    return &GImGui->DrawListSharedData;
}

void ImGui::StartMouseMovingWindow(ImGuiWindow* window)
{
    // Set ActiveId even if the _NoMove flag is set. Without it, dragging away from a window with _NoMove would activate hover on other windows.
    // We _also_ call this when clicking in a window empty space when io.ConfigWindowsMoveFromTitleBarOnly is set, but clear g.MovingWindow afterward.
    // This is because we want ActiveId to be set even when the window is not permitted to move.
    ImGuiContext& g = *GImGui;
    FocusWindow(window);
    SetActiveID(window->MoveId, window);
    g.NavDisableHighlight = true;
    g.ActiveIdClickOffset = g.IO.MouseClickedPos[0] - window->RootWindowDockTree->Pos;
    g.ActiveIdNoClearOnFocusLoss = true;
    SetActiveIdUsingAllKeyboardKeys();

    bool can_move_window = true;
    if ((window->Flags & ImGuiWindowFlags_NoMove) || (window->RootWindowDockTree->Flags & ImGuiWindowFlags_NoMove))
        can_move_window = false;
    if (ImGuiDockNode* node = window->DockNodeAsHost)
        if (node->VisibleWindow && (node->VisibleWindow->Flags & ImGuiWindowFlags_NoMove))
            can_move_window = false;
    if (can_move_window)
        g.MovingWindow = window;
}

// We use 'undock == false' when dragging from title bar to allow moving groups of floating nodes without undocking them.
void ImGui::StartMouseMovingWindowOrNode(ImGuiWindow* window, ImGuiDockNode* node, bool undock)
{
    ImGuiContext& g = *GImGui;
    bool can_undock_node = false;
    if (undock && node != NULL && node->VisibleWindow && (node->VisibleWindow->Flags & ImGuiWindowFlags_NoMove) == 0 && (node->MergedFlags & ImGuiDockNodeFlags_NoUndocking) == 0)
    {
        // Can undock if:
        // - part of a hierarchy with more than one visible node (if only one is visible, we'll just move the root window)
        // - part of a dockspace node hierarchy: so we can undock the last single visible node too (trivia: undocking from a fixed/central node will create a new node and copy windows)
        ImGuiDockNode* root_node = DockNodeGetRootNode(node);
        if (root_node->OnlyNodeWithWindows != node || root_node->CentralNode != NULL)   // -V1051 PVS-Studio thinks node should be root_node and is wrong about that.
            can_undock_node = true;
    }

    const bool clicked = IsMouseClicked(0);
    const bool dragging = IsMouseDragging(0);
    if (can_undock_node && dragging)
        DockContextQueueUndockNode(&g, node); // Will lead to DockNodeStartMouseMovingWindow() -> StartMouseMovingWindow() being called next frame
    else if (!can_undock_node && (clicked || dragging) && g.MovingWindow != window)
        StartMouseMovingWindow(window);
}

// Handle mouse moving window
// Note: moving window with the navigation keys (Square + d-pad / CTRL+TAB + Arrows) are processed in NavUpdateWindowing()
// FIXME: We don't have strong guarantee that g.MovingWindow stay synched with g.ActiveId == g.MovingWindow->MoveId.
// This is currently enforced by the fact that BeginDragDropSource() is setting all g.ActiveIdUsingXXXX flags to inhibit navigation inputs,
// but if we should more thoroughly test cases where g.ActiveId or g.MovingWindow gets changed and not the other.
void ImGui::UpdateMouseMovingWindowNewFrame()
{
    ImGuiContext& g = *GImGui;
    if (g.MovingWindow != NULL)
    {
        // We actually want to move the root window. g.MovingWindow == window we clicked on (could be a child window).
        // We track it to preserve Focus and so that generally ActiveIdWindow == MovingWindow and ActiveId == MovingWindow->MoveId for consistency.
        KeepAliveID(g.ActiveId);
        IM_ASSERT(g.MovingWindow && g.MovingWindow->RootWindowDockTree);
        ImGuiWindow* moving_window = g.MovingWindow->RootWindowDockTree;

        // When a window stop being submitted while being dragged, it may will its viewport until next Begin()
        const bool window_disappared = (!moving_window->WasActive && !moving_window->Active);
        if (g.IO.MouseDown[0] && IsMousePosValid(&g.IO.MousePos) && !window_disappared)
        {
            ImVec2 pos = g.IO.MousePos - g.ActiveIdClickOffset;
            if (moving_window->Pos.x != pos.x || moving_window->Pos.y != pos.y)
            {
                SetWindowPos(moving_window, pos, ImGuiCond_Always);
                if (moving_window->Viewport && moving_window->ViewportOwned) // Synchronize viewport immediately because some overlays may relies on clipping rectangle before we Begin() into the window.
                {
                    moving_window->Viewport->Pos = pos;
                    moving_window->Viewport->UpdateWorkRect();
                }
            }
            FocusWindow(g.MovingWindow);
        }
        else
        {
            if (!window_disappared)
            {
                // Try to merge the window back into the main viewport.
                // This works because MouseViewport should be != MovingWindow->Viewport on release (as per code in UpdateViewports)
                if (g.ConfigFlagsCurrFrame & ImGuiConfigFlags_ViewportsEnable)
                    UpdateTryMergeWindowIntoHostViewport(moving_window, g.MouseViewport);

                // Restore the mouse viewport so that we don't hover the viewport _under_ the moved window during the frame we released the mouse button.
                if (moving_window->Viewport && !IsDragDropPayloadBeingAccepted())
                    g.MouseViewport = moving_window->Viewport;

                // Clear the NoInput window flag set by the Viewport system
                if (moving_window->Viewport)
                    moving_window->Viewport->Flags &= ~ImGuiViewportFlags_NoInputs;
            }

            g.MovingWindow = NULL;
            ClearActiveID();
        }
    }
    else
    {
        // When clicking/dragging from a window that has the _NoMove flag, we still set the ActiveId in order to prevent hovering others.
        if (g.ActiveIdWindow && g.ActiveIdWindow->MoveId == g.ActiveId)
        {
            KeepAliveID(g.ActiveId);
            if (!g.IO.MouseDown[0])
                ClearActiveID();
        }
    }
}

// Initiate moving window when clicking on empty space or title bar.
// Handle left-click and right-click focus.
void ImGui::UpdateMouseMovingWindowEndFrame()
{
    ImGuiContext& g = *GImGui;
    if (g.ActiveId != 0 || g.HoveredId != 0)
        return;

    // Unless we just made a window/popup appear
    if (g.NavWindow && g.NavWindow->Appearing)
        return;

    // Click on empty space to focus window and start moving
    // (after we're done with all our widgets, so e.g. clicking on docking tab-bar which have set HoveredId already and not get us here!)
    if (g.IO.MouseClicked[0])
    {
        // Handle the edge case of a popup being closed while clicking in its empty space.
        // If we try to focus it, FocusWindow() > ClosePopupsOverWindow() will accidentally close any parent popups because they are not linked together any more.
        ImGuiWindow* root_window = g.HoveredWindow ? g.HoveredWindow->RootWindow : NULL;
        const bool is_closed_popup = root_window && (root_window->Flags & ImGuiWindowFlags_Popup) && !IsPopupOpen(root_window->PopupId, ImGuiPopupFlags_AnyPopupLevel);

        if (root_window != NULL && !is_closed_popup)
        {
            StartMouseMovingWindow(g.HoveredWindow); //-V595

            // Cancel moving if clicked outside of title bar
            if (g.IO.ConfigWindowsMoveFromTitleBarOnly)
                if (!(root_window->Flags & ImGuiWindowFlags_NoTitleBar) || root_window->DockIsActive)
                    if (!root_window->TitleBarRect().Contains(g.IO.MouseClickedPos[0]))
                        g.MovingWindow = NULL;

            // Cancel moving if clicked over an item which was disabled or inhibited by popups (note that we know HoveredId == 0 already)
            if (g.HoveredIdDisabled)
                g.MovingWindow = NULL;
        }
        else if (root_window == NULL && g.NavWindow != NULL)
        {
            // Clicking on void disable focus
            FocusWindow(NULL, ImGuiFocusRequestFlags_UnlessBelowModal);
        }
    }

    // With right mouse button we close popups without changing focus based on where the mouse is aimed
    // Instead, focus will be restored to the window under the bottom-most closed popup.
    // (The left mouse button path calls FocusWindow on the hovered window, which will lead NewFrame->ClosePopupsOverWindow to trigger)
    if (g.IO.MouseClicked[1])
    {
        // Find the top-most window between HoveredWindow and the top-most Modal Window.
        // This is where we can trim the popup stack.
        ImGuiWindow* modal = GetTopMostPopupModal();
        bool hovered_window_above_modal = g.HoveredWindow && (modal == NULL || IsWindowAbove(g.HoveredWindow, modal));
        ClosePopupsOverWindow(hovered_window_above_modal ? g.HoveredWindow : modal, true);
    }
}

// This is called during NewFrame()->UpdateViewportsNewFrame() only.
// Need to keep in sync with SetWindowPos()
static void TranslateWindow(ImGuiWindow* window, const ImVec2& delta)
{
    window->Pos += delta;
    window->ClipRect.Translate(delta);
    window->OuterRectClipped.Translate(delta);
    window->InnerRect.Translate(delta);
    window->DC.CursorPos += delta;
    window->DC.CursorStartPos += delta;
    window->DC.CursorMaxPos += delta;
    window->DC.IdealMaxPos += delta;
}

static void ScaleWindow(ImGuiWindow* window, float scale)
{
    ImVec2 origin = window->Viewport->Pos;
    window->Pos = ImFloor((window->Pos - origin) * scale + origin);
    window->Size = ImTrunc(window->Size * scale);
    window->SizeFull = ImTrunc(window->SizeFull * scale);
    window->ContentSize = ImTrunc(window->ContentSize * scale);
}

static bool IsWindowActiveAndVisible(ImGuiWindow* window)
{
    return (window->Active) && (!window->Hidden);
}

// The reason this is exposed in imgui_internal.h is: on touch-based system that don't have hovering, we want to dispatch inputs to the right target (imgui vs imgui+app)
void ImGui::UpdateHoveredWindowAndCaptureFlags()
{
    ImGuiContext& g = *GImGui;
    ImGuiIO& io = g.IO;
    g.WindowsHoverPadding = ImMax(g.Style.TouchExtraPadding, ImVec2(WINDOWS_HOVER_PADDING, WINDOWS_HOVER_PADDING));

    // Find the window hovered by mouse:
    // - Child windows can extend beyond the limit of their parent so we need to derive HoveredRootWindow from HoveredWindow.
    // - When moving a window we can skip the search, which also conveniently bypasses the fact that window->WindowRectClipped is lagging as this point of the frame.
    // - We also support the moved window toggling the NoInputs flag after moving has started in order to be able to detect windows below it, which is useful for e.g. docking mechanisms.
    bool clear_hovered_windows = false;
    FindHoveredWindow();
    IM_ASSERT(g.HoveredWindow == NULL || g.HoveredWindow == g.MovingWindow || g.HoveredWindow->Viewport == g.MouseViewport);

    // Modal windows prevents mouse from hovering behind them.
    ImGuiWindow* modal_window = GetTopMostPopupModal();
    if (modal_window && g.HoveredWindow && !IsWindowWithinBeginStackOf(g.HoveredWindow->RootWindow, modal_window)) // FIXME-MERGE: RootWindowDockTree ?
        clear_hovered_windows = true;

    // Disabled mouse?
    if (io.ConfigFlags & ImGuiConfigFlags_NoMouse)
        clear_hovered_windows = true;

    // We track click ownership. When clicked outside of a window the click is owned by the application and
    // won't report hovering nor request capture even while dragging over our windows afterward.
    const bool has_open_popup = (g.OpenPopupStack.Size > 0);
    const bool has_open_modal = (modal_window != NULL);
    int mouse_earliest_down = -1;
    bool mouse_any_down = false;
    for (int i = 0; i < IM_ARRAYSIZE(io.MouseDown); i++)
    {
        if (io.MouseClicked[i])
        {
            io.MouseDownOwned[i] = (g.HoveredWindow != NULL) || has_open_popup;
            io.MouseDownOwnedUnlessPopupClose[i] = (g.HoveredWindow != NULL) || has_open_modal;
        }
        mouse_any_down |= io.MouseDown[i];
        if (io.MouseDown[i])
            if (mouse_earliest_down == -1 || io.MouseClickedTime[i] < io.MouseClickedTime[mouse_earliest_down])
                mouse_earliest_down = i;
    }
    const bool mouse_avail = (mouse_earliest_down == -1) || io.MouseDownOwned[mouse_earliest_down];
    const bool mouse_avail_unless_popup_close = (mouse_earliest_down == -1) || io.MouseDownOwnedUnlessPopupClose[mouse_earliest_down];

    // If mouse was first clicked outside of ImGui bounds we also cancel out hovering.
    // FIXME: For patterns of drag and drop across OS windows, we may need to rework/remove this test (first committed 311c0ca9 on 2015/02)
    const bool mouse_dragging_extern_payload = g.DragDropActive && (g.DragDropSourceFlags & ImGuiDragDropFlags_SourceExtern) != 0;
    if (!mouse_avail && !mouse_dragging_extern_payload)
        clear_hovered_windows = true;

    if (clear_hovered_windows)
        g.HoveredWindow = g.HoveredWindowUnderMovingWindow = NULL;

    // Update io.WantCaptureMouse for the user application (true = dispatch mouse info to Dear ImGui only, false = dispatch mouse to Dear ImGui + underlying app)
    // Update io.WantCaptureMouseAllowPopupClose (experimental) to give a chance for app to react to popup closure with a drag
    if (g.WantCaptureMouseNextFrame != -1)
    {
        io.WantCaptureMouse = io.WantCaptureMouseUnlessPopupClose = (g.WantCaptureMouseNextFrame != 0);
    }
    else
    {
        io.WantCaptureMouse = (mouse_avail && (g.HoveredWindow != NULL || mouse_any_down)) || has_open_popup;
        io.WantCaptureMouseUnlessPopupClose = (mouse_avail_unless_popup_close && (g.HoveredWindow != NULL || mouse_any_down)) || has_open_modal;
    }

    // Update io.WantCaptureKeyboard for the user application (true = dispatch keyboard info to Dear ImGui only, false = dispatch keyboard info to Dear ImGui + underlying app)
    if (g.WantCaptureKeyboardNextFrame != -1)
        io.WantCaptureKeyboard = (g.WantCaptureKeyboardNextFrame != 0);
    else
        io.WantCaptureKeyboard = (g.ActiveId != 0) || (modal_window != NULL);
    if (io.NavActive && (io.ConfigFlags & ImGuiConfigFlags_NavEnableKeyboard) && !(io.ConfigFlags & ImGuiConfigFlags_NavNoCaptureKeyboard))
        io.WantCaptureKeyboard = true;

    // Update io.WantTextInput flag, this is to allow systems without a keyboard (e.g. mobile, hand-held) to show a software keyboard if possible
    io.WantTextInput = (g.WantTextInputNextFrame != -1) ? (g.WantTextInputNextFrame != 0) : false;
}

void ImGui::NewFrame()
{
    IM_ASSERT(GImGui != NULL && "No current context. Did you call ImGui::CreateContext() and ImGui::SetCurrentContext() ?");
    ImGuiContext& g = *GImGui;

    // Remove pending delete hooks before frame start.
    // This deferred removal avoid issues of removal while iterating the hook vector
    for (int n = g.Hooks.Size - 1; n >= 0; n--)
        if (g.Hooks[n].Type == ImGuiContextHookType_PendingRemoval_)
            g.Hooks.erase(&g.Hooks[n]);

    CallContextHooks(&g, ImGuiContextHookType_NewFramePre);

    // Check and assert for various common IO and Configuration mistakes
    g.ConfigFlagsLastFrame = g.ConfigFlagsCurrFrame;
    ErrorCheckNewFrameSanityChecks();
    g.ConfigFlagsCurrFrame = g.IO.ConfigFlags;

    // Load settings on first frame, save settings when modified (after a delay)
    UpdateSettings();

    g.Time += g.IO.DeltaTime;
    g.WithinFrameScope = true;
    g.FrameCount += 1;
    g.TooltipOverrideCount = 0;
    g.WindowsActiveCount = 0;
    g.MenusIdSubmittedThisFrame.resize(0);

    // Calculate frame-rate for the user, as a purely luxurious feature
    g.FramerateSecPerFrameAccum += g.IO.DeltaTime - g.FramerateSecPerFrame[g.FramerateSecPerFrameIdx];
    g.FramerateSecPerFrame[g.FramerateSecPerFrameIdx] = g.IO.DeltaTime;
    g.FramerateSecPerFrameIdx = (g.FramerateSecPerFrameIdx + 1) % IM_ARRAYSIZE(g.FramerateSecPerFrame);
    g.FramerateSecPerFrameCount = ImMin(g.FramerateSecPerFrameCount + 1, IM_ARRAYSIZE(g.FramerateSecPerFrame));
    g.IO.Framerate = (g.FramerateSecPerFrameAccum > 0.0f) ? (1.0f / (g.FramerateSecPerFrameAccum / (float)g.FramerateSecPerFrameCount)) : FLT_MAX;

    // Process input queue (trickle as many events as possible), turn events into writes to IO structure
    g.InputEventsTrail.resize(0);
    UpdateInputEvents(g.IO.ConfigInputTrickleEventQueue);

    // Update viewports (after processing input queue, so io.MouseHoveredViewport is set)
    UpdateViewportsNewFrame();

    // Setup current font and draw list shared data
    // FIXME-VIEWPORT: the concept of a single ClipRectFullscreen is not ideal!
    g.IO.Fonts->Locked = true;
    SetCurrentFont(GetDefaultFont());
    IM_ASSERT(g.Font->IsLoaded());
    ImRect virtual_space(FLT_MAX, FLT_MAX, -FLT_MAX, -FLT_MAX);
    for (ImGuiViewportP* viewport : g.Viewports)
        virtual_space.Add(viewport->GetMainRect());
    g.DrawListSharedData.ClipRectFullscreen = virtual_space.ToVec4();
    g.DrawListSharedData.CurveTessellationTol = g.Style.CurveTessellationTol;
    g.DrawListSharedData.SetCircleTessellationMaxError(g.Style.CircleTessellationMaxError);
    g.DrawListSharedData.InitialFlags = ImDrawListFlags_None;
    if (g.Style.AntiAliasedLines)
        g.DrawListSharedData.InitialFlags |= ImDrawListFlags_AntiAliasedLines;
    if (g.Style.AntiAliasedLinesUseTex && !(g.Font->ContainerAtlas->Flags & ImFontAtlasFlags_NoBakedLines))
        g.DrawListSharedData.InitialFlags |= ImDrawListFlags_AntiAliasedLinesUseTex;
    if (g.Style.AntiAliasedFill)
        g.DrawListSharedData.InitialFlags |= ImDrawListFlags_AntiAliasedFill;
    if (g.IO.BackendFlags & ImGuiBackendFlags_RendererHasVtxOffset)
        g.DrawListSharedData.InitialFlags |= ImDrawListFlags_AllowVtxOffset;

    // Mark rendering data as invalid to prevent user who may have a handle on it to use it.
    for (ImGuiViewportP* viewport : g.Viewports)
    {
        viewport->DrawData = NULL;
        viewport->DrawDataP.Valid = false;
    }

    // Drag and drop keep the source ID alive so even if the source disappear our state is consistent
    if (g.DragDropActive && g.DragDropPayload.SourceId == g.ActiveId)
        KeepAliveID(g.DragDropPayload.SourceId);

    // Update HoveredId data
    if (!g.HoveredIdPreviousFrame)
        g.HoveredIdTimer = 0.0f;
    if (!g.HoveredIdPreviousFrame || (g.HoveredId && g.ActiveId == g.HoveredId))
        g.HoveredIdNotActiveTimer = 0.0f;
    if (g.HoveredId)
        g.HoveredIdTimer += g.IO.DeltaTime;
    if (g.HoveredId && g.ActiveId != g.HoveredId)
        g.HoveredIdNotActiveTimer += g.IO.DeltaTime;
    g.HoveredIdPreviousFrame = g.HoveredId;
    g.HoveredId = 0;
    g.HoveredIdAllowOverlap = false;
    g.HoveredIdDisabled = false;

    // Clear ActiveID if the item is not alive anymore.
    // In 1.87, the common most call to KeepAliveID() was moved from GetID() to ItemAdd().
    // As a result, custom widget using ButtonBehavior() _without_ ItemAdd() need to call KeepAliveID() themselves.
    if (g.ActiveId != 0 && g.ActiveIdIsAlive != g.ActiveId && g.ActiveIdPreviousFrame == g.ActiveId)
    {
        IMGUI_DEBUG_LOG_ACTIVEID("NewFrame(): ClearActiveID() because it isn't marked alive anymore!\n");
        ClearActiveID();
    }

    // Update ActiveId data (clear reference to active widget if the widget isn't alive anymore)
    if (g.ActiveId)
        g.ActiveIdTimer += g.IO.DeltaTime;
    g.LastActiveIdTimer += g.IO.DeltaTime;
    g.ActiveIdPreviousFrame = g.ActiveId;
    g.ActiveIdPreviousFrameWindow = g.ActiveIdWindow;
    g.ActiveIdPreviousFrameHasBeenEditedBefore = g.ActiveIdHasBeenEditedBefore;
    g.ActiveIdIsAlive = 0;
    g.ActiveIdHasBeenEditedThisFrame = false;
    g.ActiveIdPreviousFrameIsAlive = false;
    g.ActiveIdIsJustActivated = false;
    if (g.TempInputId != 0 && g.ActiveId != g.TempInputId)
        g.TempInputId = 0;
    if (g.ActiveId == 0)
    {
        g.ActiveIdUsingNavDirMask = 0x00;
        g.ActiveIdUsingAllKeyboardKeys = false;
#ifndef IMGUI_DISABLE_OBSOLETE_KEYIO
        g.ActiveIdUsingNavInputMask = 0x00;
#endif
    }

#ifndef IMGUI_DISABLE_OBSOLETE_KEYIO
    if (g.ActiveId == 0)
        g.ActiveIdUsingNavInputMask = 0;
    else if (g.ActiveIdUsingNavInputMask != 0)
    {
        // If your custom widget code used:                 { g.ActiveIdUsingNavInputMask |= (1 << ImGuiNavInput_Cancel); }
        // Since IMGUI_VERSION_NUM >= 18804 it should be:   { SetKeyOwner(ImGuiKey_Escape, g.ActiveId); SetKeyOwner(ImGuiKey_NavGamepadCancel, g.ActiveId); }
        if (g.ActiveIdUsingNavInputMask & (1 << ImGuiNavInput_Cancel))
            SetKeyOwner(ImGuiKey_Escape, g.ActiveId);
        if (g.ActiveIdUsingNavInputMask & ~(1 << ImGuiNavInput_Cancel))
            IM_ASSERT(0); // Other values unsupported
    }
#endif

    // Record when we have been stationary as this state is preserved while over same item.
    // FIXME: The way this is expressed means user cannot alter HoverStationaryDelay during the frame to use varying values.
    // To allow this we should store HoverItemMaxStationaryTime+ID and perform the >= check in IsItemHovered() function.
    if (g.HoverItemDelayId != 0 && g.MouseStationaryTimer >= g.Style.HoverStationaryDelay)
        g.HoverItemUnlockedStationaryId = g.HoverItemDelayId;
    else if (g.HoverItemDelayId == 0)
        g.HoverItemUnlockedStationaryId = 0;
    if (g.HoveredWindow != NULL && g.MouseStationaryTimer >= g.Style.HoverStationaryDelay)
        g.HoverWindowUnlockedStationaryId = g.HoveredWindow->ID;
    else if (g.HoveredWindow == NULL)
        g.HoverWindowUnlockedStationaryId = 0;

    // Update hover delay for IsItemHovered() with delays and tooltips
    g.HoverItemDelayIdPreviousFrame = g.HoverItemDelayId;
    if (g.HoverItemDelayId != 0)
    {
        g.HoverItemDelayTimer += g.IO.DeltaTime;
        g.HoverItemDelayClearTimer = 0.0f;
        g.HoverItemDelayId = 0;
    }
    else if (g.HoverItemDelayTimer > 0.0f)
    {
        // This gives a little bit of leeway before clearing the hover timer, allowing mouse to cross gaps
        // We could expose 0.25f as style.HoverClearDelay but I am not sure of the logic yet, this is particularly subtle.
        g.HoverItemDelayClearTimer += g.IO.DeltaTime;
        if (g.HoverItemDelayClearTimer >= ImMax(0.25f, g.IO.DeltaTime * 2.0f)) // ~7 frames at 30 Hz + allow for low framerate
            g.HoverItemDelayTimer = g.HoverItemDelayClearTimer = 0.0f; // May want a decaying timer, in which case need to clamp at max first, based on max of caller last requested timer.
    }

    // Drag and drop
    g.DragDropAcceptIdPrev = g.DragDropAcceptIdCurr;
    g.DragDropAcceptIdCurr = 0;
    g.DragDropAcceptIdCurrRectSurface = FLT_MAX;
    g.DragDropWithinSource = false;
    g.DragDropWithinTarget = false;
    g.DragDropHoldJustPressedId = 0;

    // Close popups on focus lost (currently wip/opt-in)
    //if (g.IO.AppFocusLost)
    //    ClosePopupsExceptModals();

    // Update keyboard input state
    UpdateKeyboardInputs();

    //IM_ASSERT(g.IO.KeyCtrl == IsKeyDown(ImGuiKey_LeftCtrl) || IsKeyDown(ImGuiKey_RightCtrl));
    //IM_ASSERT(g.IO.KeyShift == IsKeyDown(ImGuiKey_LeftShift) || IsKeyDown(ImGuiKey_RightShift));
    //IM_ASSERT(g.IO.KeyAlt == IsKeyDown(ImGuiKey_LeftAlt) || IsKeyDown(ImGuiKey_RightAlt));
    //IM_ASSERT(g.IO.KeySuper == IsKeyDown(ImGuiKey_LeftSuper) || IsKeyDown(ImGuiKey_RightSuper));

    // Update gamepad/keyboard navigation
    NavUpdate();

    // Update mouse input state
    UpdateMouseInputs();

    // Undocking
    // (needs to be before UpdateMouseMovingWindowNewFrame so the window is already offset and following the mouse on the detaching frame)
    DockContextNewFrameUpdateUndocking(&g);

    // Find hovered window
    // (needs to be before UpdateMouseMovingWindowNewFrame so we fill g.HoveredWindowUnderMovingWindow on the mouse release frame)
    UpdateHoveredWindowAndCaptureFlags();

    // Handle user moving window with mouse (at the beginning of the frame to avoid input lag or sheering)
    UpdateMouseMovingWindowNewFrame();

    // Background darkening/whitening
    if (GetTopMostPopupModal() != NULL || (g.NavWindowingTarget != NULL && g.NavWindowingHighlightAlpha > 0.0f))
        g.DimBgRatio = ImMin(g.DimBgRatio + g.IO.DeltaTime * 6.0f, 1.0f);
    else
        g.DimBgRatio = ImMax(g.DimBgRatio - g.IO.DeltaTime * 10.0f, 0.0f);

    g.MouseCursor = ImGuiMouseCursor_Arrow;
    g.WantCaptureMouseNextFrame = g.WantCaptureKeyboardNextFrame = g.WantTextInputNextFrame = -1;

    // Platform IME data: reset for the frame
    g.PlatformImeDataPrev = g.PlatformImeData;
    g.PlatformImeData.WantVisible = false;

    // Mouse wheel scrolling, scale
    UpdateMouseWheel();

    // Mark all windows as not visible and compact unused memory.
    IM_ASSERT(g.WindowsFocusOrder.Size <= g.Windows.Size);
    const float memory_compact_start_time = (g.GcCompactAll || g.IO.ConfigMemoryCompactTimer < 0.0f) ? FLT_MAX : (float)g.Time - g.IO.ConfigMemoryCompactTimer;
    for (ImGuiWindow* window : g.Windows)
    {
        window->WasActive = window->Active;
        window->Active = false;
        window->WriteAccessed = false;
        window->BeginCountPreviousFrame = window->BeginCount;
        window->BeginCount = 0;

        // Garbage collect transient buffers of recently unused windows
        if (!window->WasActive && !window->MemoryCompacted && window->LastTimeActive < memory_compact_start_time)
            GcCompactTransientWindowBuffers(window);
    }

    // Garbage collect transient buffers of recently unused tables
    for (int i = 0; i < g.TablesLastTimeActive.Size; i++)
        if (g.TablesLastTimeActive[i] >= 0.0f && g.TablesLastTimeActive[i] < memory_compact_start_time)
            TableGcCompactTransientBuffers(g.Tables.GetByIndex(i));
    for (ImGuiTableTempData& table_temp_data : g.TablesTempData)
        if (table_temp_data.LastTimeActive >= 0.0f && table_temp_data.LastTimeActive < memory_compact_start_time)
            TableGcCompactTransientBuffers(&table_temp_data);
    if (g.GcCompactAll)
        GcCompactTransientMiscBuffers();
    g.GcCompactAll = false;

    // Closing the focused window restore focus to the first active root window in descending z-order
    if (g.NavWindow && !g.NavWindow->WasActive)
        FocusTopMostWindowUnderOne(NULL, NULL, NULL, ImGuiFocusRequestFlags_RestoreFocusedChild);

    // No window should be open at the beginning of the frame.
    // But in order to allow the user to call NewFrame() multiple times without calling Render(), we are doing an explicit clear.
    g.CurrentWindowStack.resize(0);
    g.BeginPopupStack.resize(0);
    g.ItemFlagsStack.resize(0);
    g.ItemFlagsStack.push_back(ImGuiItemFlags_None);
    g.GroupStack.resize(0);

    // Docking
    DockContextNewFrameUpdateDocking(&g);

    // [DEBUG] Update debug features
    UpdateDebugToolItemPicker();
    UpdateDebugToolStackQueries();
    if (g.DebugLocateFrames > 0 && --g.DebugLocateFrames == 0)
        g.DebugLocateId = 0;
    if (g.DebugLogClipperAutoDisableFrames > 0 && --g.DebugLogClipperAutoDisableFrames == 0)
    {
        DebugLog("(Auto-disabled ImGuiDebugLogFlags_EventClipper to avoid spamming)\n");
        g.DebugLogFlags &= ~ImGuiDebugLogFlags_EventClipper;
    }

    // Create implicit/fallback window - which we will only render it if the user has added something to it.
    // We don't use "Debug" to avoid colliding with user trying to create a "Debug" window with custom flags.
    // This fallback is particularly important as it prevents ImGui:: calls from crashing.
    g.WithinFrameScopeWithImplicitWindow = true;
    SetNextWindowSize(ImVec2(400, 400), ImGuiCond_FirstUseEver);
    Begin("Debug##Default");
    IM_ASSERT(g.CurrentWindow->IsFallbackWindow == true);

    // [DEBUG] When io.ConfigDebugBeginReturnValue is set, we make Begin()/BeginChild() return false at different level of the window-stack,
    // allowing to validate correct Begin/End behavior in user code.
    if (g.IO.ConfigDebugBeginReturnValueLoop)
        g.DebugBeginReturnValueCullDepth = (g.DebugBeginReturnValueCullDepth == -1) ? 0 : ((g.DebugBeginReturnValueCullDepth + ((g.FrameCount % 4) == 0 ? 1 : 0)) % 10);
    else
        g.DebugBeginReturnValueCullDepth = -1;

    CallContextHooks(&g, ImGuiContextHookType_NewFramePost);
}

// FIXME: Add a more explicit sort order in the window structure.
static int IMGUI_CDECL ChildWindowComparer(const void* lhs, const void* rhs)
{
    const ImGuiWindow* const a = *(const ImGuiWindow* const *)lhs;
    const ImGuiWindow* const b = *(const ImGuiWindow* const *)rhs;
    if (int d = (a->Flags & ImGuiWindowFlags_Popup) - (b->Flags & ImGuiWindowFlags_Popup))
        return d;
    if (int d = (a->Flags & ImGuiWindowFlags_Tooltip) - (b->Flags & ImGuiWindowFlags_Tooltip))
        return d;
    return (a->BeginOrderWithinParent - b->BeginOrderWithinParent);
}

static void AddWindowToSortBuffer(ImVector<ImGuiWindow*>* out_sorted_windows, ImGuiWindow* window)
{
    out_sorted_windows->push_back(window);
    if (window->Active)
    {
        int count = window->DC.ChildWindows.Size;
        ImQsort(window->DC.ChildWindows.Data, (size_t)count, sizeof(ImGuiWindow*), ChildWindowComparer);
        for (int i = 0; i < count; i++)
        {
            ImGuiWindow* child = window->DC.ChildWindows[i];
            if (child->Active)
                AddWindowToSortBuffer(out_sorted_windows, child);
        }
    }
}

static void AddWindowToDrawData(ImGuiWindow* window, int layer)
{
    ImGuiContext& g = *GImGui;
    ImGuiViewportP* viewport = window->Viewport;
    IM_ASSERT(viewport != NULL);
    g.IO.MetricsRenderWindows++;
    if (window->DrawList->_Splitter._Count > 1)
        window->DrawList->ChannelsMerge(); // Merge if user forgot to merge back. Also required in Docking branch for ImGuiWindowFlags_DockNodeHost windows.
    ImGui::AddDrawListToDrawDataEx(&viewport->DrawDataP, viewport->DrawDataBuilder.Layers[layer], window->DrawList);
    for (ImGuiWindow* child : window->DC.ChildWindows)
        if (IsWindowActiveAndVisible(child)) // Clipped children may have been marked not active
            AddWindowToDrawData(child, layer);
}

static inline int GetWindowDisplayLayer(ImGuiWindow* window)
{
    return (window->Flags & ImGuiWindowFlags_Tooltip) ? 1 : 0;
}

// Layer is locked for the root window, however child windows may use a different viewport (e.g. extruding menu)
static inline void AddRootWindowToDrawData(ImGuiWindow* window)
{
    AddWindowToDrawData(window, GetWindowDisplayLayer(window));
}

static void FlattenDrawDataIntoSingleLayer(ImDrawDataBuilder* builder)
{
    int n = builder->Layers[0]->Size;
    int full_size = n;
    for (int i = 1; i < IM_ARRAYSIZE(builder->Layers); i++)
        full_size += builder->Layers[i]->Size;
    builder->Layers[0]->resize(full_size);
    for (int layer_n = 1; layer_n < IM_ARRAYSIZE(builder->Layers); layer_n++)
    {
        ImVector<ImDrawList*>* layer = builder->Layers[layer_n];
        if (layer->empty())
            continue;
        memcpy(builder->Layers[0]->Data + n, layer->Data, layer->Size * sizeof(ImDrawList*));
        n += layer->Size;
        layer->resize(0);
    }
}

static void InitViewportDrawData(ImGuiViewportP* viewport)
{
    ImGuiIO& io = ImGui::GetIO();
    ImDrawData* draw_data = &viewport->DrawDataP;

    viewport->DrawData = draw_data; // Make publicly accessible
    viewport->DrawDataBuilder.Layers[0] = &draw_data->CmdLists;
    viewport->DrawDataBuilder.Layers[1] = &viewport->DrawDataBuilder.LayerData1;
    viewport->DrawDataBuilder.Layers[0]->resize(0);
    viewport->DrawDataBuilder.Layers[1]->resize(0);

    // When minimized, we report draw_data->DisplaySize as zero to be consistent with non-viewport mode,
    // and to allow applications/backends to easily skip rendering.
    // FIXME: Note that we however do NOT attempt to report "zero drawlist / vertices" into the ImDrawData structure.
    // This is because the work has been done already, and its wasted! We should fix that and add optimizations for
    // it earlier in the pipeline, rather than pretend to hide the data at the end of the pipeline.
    const bool is_minimized = (viewport->Flags & ImGuiViewportFlags_IsMinimized) != 0;

    draw_data->Valid = true;
    draw_data->CmdListsCount = 0;
    draw_data->TotalVtxCount = draw_data->TotalIdxCount = 0;
    draw_data->DisplayPos = viewport->Pos;
    draw_data->DisplaySize = is_minimized ? ImVec2(0.0f, 0.0f) : viewport->Size;
    draw_data->FramebufferScale = io.DisplayFramebufferScale; // FIXME-VIEWPORT: This may vary on a per-monitor/viewport basis?
    draw_data->OwnerViewport = viewport;
}

// Push a clipping rectangle for both ImGui logic (hit-testing etc.) and low-level ImDrawList rendering.
// - When using this function it is sane to ensure that float are perfectly rounded to integer values,
//   so that e.g. (int)(max.x-min.x) in user's render produce correct result.
// - If the code here changes, may need to update code of functions like NextColumn() and PushColumnClipRect():
//   some frequently called functions which to modify both channels and clipping simultaneously tend to use the
//   more specialized SetWindowClipRectBeforeSetChannel() to avoid extraneous updates of underlying ImDrawCmds.
void ImGui::PushClipRect(const ImVec2& clip_rect_min, const ImVec2& clip_rect_max, bool intersect_with_current_clip_rect)
{
    ImGuiWindow* window = GetCurrentWindow();
    window->DrawList->PushClipRect(clip_rect_min, clip_rect_max, intersect_with_current_clip_rect);
    window->ClipRect = window->DrawList->_ClipRectStack.back();
}

void ImGui::PopClipRect()
{
    ImGuiWindow* window = GetCurrentWindow();
    window->DrawList->PopClipRect();
    window->ClipRect = window->DrawList->_ClipRectStack.back();
}

static ImGuiWindow* FindFrontMostVisibleChildWindow(ImGuiWindow* window)
{
    for (int n = window->DC.ChildWindows.Size - 1; n >= 0; n--)
        if (IsWindowActiveAndVisible(window->DC.ChildWindows[n]))
            return FindFrontMostVisibleChildWindow(window->DC.ChildWindows[n]);
    return window;
}

static void ImGui::RenderDimmedBackgroundBehindWindow(ImGuiWindow* window, ImU32 col)
{
    if ((col & IM_COL32_A_MASK) == 0)
        return;

    ImGuiViewportP* viewport = window->Viewport;
    ImRect viewport_rect = viewport->GetMainRect();

    // Draw behind window by moving the draw command at the FRONT of the draw list
    {
        // Draw list have been trimmed already, hence the explicit recreation of a draw command if missing.
        // FIXME: This is creating complication, might be simpler if we could inject a drawlist in drawdata at a given position and not attempt to manipulate ImDrawCmd order.
        ImDrawList* draw_list = window->RootWindowDockTree->DrawList;
        draw_list->ChannelsMerge();
        if (draw_list->CmdBuffer.Size == 0)
            draw_list->AddDrawCmd();
        draw_list->PushClipRect(viewport_rect.Min - ImVec2(1, 1), viewport_rect.Max + ImVec2(1, 1), false); // FIXME: Need to stricty ensure ImDrawCmd are not merged (ElemCount==6 checks below will verify that)
        draw_list->AddRectFilled(viewport_rect.Min, viewport_rect.Max, col);
        ImDrawCmd cmd = draw_list->CmdBuffer.back();
        IM_ASSERT(cmd.ElemCount == 6);
        draw_list->CmdBuffer.pop_back();
        draw_list->CmdBuffer.push_front(cmd);
        draw_list->AddDrawCmd(); // We need to create a command as CmdBuffer.back().IdxOffset won't be correct if we append to same command.
        draw_list->PopClipRect();
    }

    // Draw over sibling docking nodes in a same docking tree
    if (window->RootWindow->DockIsActive)
    {
        ImDrawList* draw_list = FindFrontMostVisibleChildWindow(window->RootWindowDockTree)->DrawList;
        draw_list->ChannelsMerge();
        if (draw_list->CmdBuffer.Size == 0)
            draw_list->AddDrawCmd();
        draw_list->PushClipRect(viewport_rect.Min, viewport_rect.Max, false);
        RenderRectFilledWithHole(draw_list, window->RootWindowDockTree->Rect(), window->RootWindow->Rect(), col, 0.0f);// window->RootWindowDockTree->WindowRounding);
        draw_list->PopClipRect();
    }
}

ImGuiWindow* ImGui::FindBottomMostVisibleWindowWithinBeginStack(ImGuiWindow* parent_window)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* bottom_most_visible_window = parent_window;
    for (int i = FindWindowDisplayIndex(parent_window); i >= 0; i--)
    {
        ImGuiWindow* window = g.Windows[i];
        if (window->Flags & ImGuiWindowFlags_ChildWindow)
            continue;
        if (!IsWindowWithinBeginStackOf(window, parent_window))
            break;
        if (IsWindowActiveAndVisible(window) && GetWindowDisplayLayer(window) <= GetWindowDisplayLayer(parent_window))
            bottom_most_visible_window = window;
    }
    return bottom_most_visible_window;
}

// Important: AddWindowToDrawData() has not been called yet, meaning DockNodeHost windows needs a DrawList->ChannelsMerge() before usage.
// We call ChannelsMerge() lazily here at it is faster that doing a full iteration of g.Windows[] prior to calling RenderDimmedBackgrounds().
static void ImGui::RenderDimmedBackgrounds()
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* modal_window = GetTopMostAndVisiblePopupModal();
    if (g.DimBgRatio <= 0.0f && g.NavWindowingHighlightAlpha <= 0.0f)
        return;
    const bool dim_bg_for_modal = (modal_window != NULL);
    const bool dim_bg_for_window_list = (g.NavWindowingTargetAnim != NULL && g.NavWindowingTargetAnim->Active);
    if (!dim_bg_for_modal && !dim_bg_for_window_list)
        return;

    ImGuiViewport* viewports_already_dimmed[2] = { NULL, NULL };
    if (dim_bg_for_modal)
    {
        // Draw dimming behind modal or a begin stack child, whichever comes first in draw order.
        ImGuiWindow* dim_behind_window = FindBottomMostVisibleWindowWithinBeginStack(modal_window);
        RenderDimmedBackgroundBehindWindow(dim_behind_window, GetColorU32(ImGuiCol_ModalWindowDimBg, g.DimBgRatio));
        viewports_already_dimmed[0] = modal_window->Viewport;
    }
    else if (dim_bg_for_window_list)
    {
        // Draw dimming behind CTRL+Tab target window and behind CTRL+Tab UI window
        RenderDimmedBackgroundBehindWindow(g.NavWindowingTargetAnim, GetColorU32(ImGuiCol_NavWindowingDimBg, g.DimBgRatio));
        if (g.NavWindowingListWindow != NULL && g.NavWindowingListWindow->Viewport && g.NavWindowingListWindow->Viewport != g.NavWindowingTargetAnim->Viewport)
            RenderDimmedBackgroundBehindWindow(g.NavWindowingListWindow, GetColorU32(ImGuiCol_NavWindowingDimBg, g.DimBgRatio));
        viewports_already_dimmed[0] = g.NavWindowingTargetAnim->Viewport;
        viewports_already_dimmed[1] = g.NavWindowingListWindow ? g.NavWindowingListWindow->Viewport : NULL;

        // Draw border around CTRL+Tab target window
        ImGuiWindow* window = g.NavWindowingTargetAnim;
        ImGuiViewport* viewport = window->Viewport;
        float distance = g.FontSize;
        ImRect bb = window->Rect();
        bb.Expand(distance);
        if (bb.GetWidth() >= viewport->Size.x && bb.GetHeight() >= viewport->Size.y)
            bb.Expand(-distance - 1.0f); // If a window fits the entire viewport, adjust its highlight inward
        window->DrawList->ChannelsMerge();
        if (window->DrawList->CmdBuffer.Size == 0)
            window->DrawList->AddDrawCmd();
        window->DrawList->PushClipRect(viewport->Pos, viewport->Pos + viewport->Size);
        window->DrawList->AddRect(bb.Min, bb.Max, GetColorU32(ImGuiCol_NavWindowingHighlight, g.NavWindowingHighlightAlpha), window->WindowRounding, 0, 3.0f);
        window->DrawList->PopClipRect();
    }

    // Draw dimming background on _other_ viewports than the ones our windows are in
    for (ImGuiViewportP* viewport : g.Viewports)
    {
        if (viewport == viewports_already_dimmed[0] || viewport == viewports_already_dimmed[1])
            continue;
        if (modal_window && viewport->Window && IsWindowAbove(viewport->Window, modal_window))
            continue;
        ImDrawList* draw_list = GetForegroundDrawList(viewport);
        const ImU32 dim_bg_col = GetColorU32(dim_bg_for_modal ? ImGuiCol_ModalWindowDimBg : ImGuiCol_NavWindowingDimBg, g.DimBgRatio);
        draw_list->AddRectFilled(viewport->Pos, viewport->Pos + viewport->Size, dim_bg_col);
    }
}

// This is normally called by Render(). You may want to call it directly if you want to avoid calling Render() but the gain will be very minimal.
void ImGui::EndFrame()
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(g.Initialized);

    // Don't process EndFrame() multiple times.
    if (g.FrameCountEnded == g.FrameCount)
        return;
    IM_ASSERT(g.WithinFrameScope && "Forgot to call ImGui::NewFrame()?");

    CallContextHooks(&g, ImGuiContextHookType_EndFramePre);

    ErrorCheckEndFrameSanityChecks();

    // Notify Platform/OS when our Input Method Editor cursor has moved (e.g. CJK inputs using Microsoft IME)
    ImGuiPlatformImeData* ime_data = &g.PlatformImeData;
    if (g.IO.SetPlatformImeDataFn && memcmp(ime_data, &g.PlatformImeDataPrev, sizeof(ImGuiPlatformImeData)) != 0)
    {
        ImGuiViewport* viewport = FindViewportByID(g.PlatformImeViewport);
        IMGUI_DEBUG_LOG_IO("[io] Calling io.SetPlatformImeDataFn(): WantVisible: %d, InputPos (%.2f,%.2f)\n", ime_data->WantVisible, ime_data->InputPos.x, ime_data->InputPos.y);
        if (viewport == NULL)
            viewport = GetMainViewport();
#ifndef IMGUI_DISABLE_OBSOLETE_FUNCTIONS
        if (viewport->PlatformHandleRaw == NULL && g.IO.ImeWindowHandle != NULL)
        {
            viewport->PlatformHandleRaw = g.IO.ImeWindowHandle;
            g.IO.SetPlatformImeDataFn(viewport, ime_data);
            viewport->PlatformHandleRaw = NULL;
        }
        else
#endif
        {
            g.IO.SetPlatformImeDataFn(viewport, ime_data);
        }
    }

    // Hide implicit/fallback "Debug" window if it hasn't been used
    g.WithinFrameScopeWithImplicitWindow = false;
    if (g.CurrentWindow && !g.CurrentWindow->WriteAccessed)
        g.CurrentWindow->Active = false;
    End();

    // Update navigation: CTRL+Tab, wrap-around requests
    NavEndFrame();

    // Update docking
    DockContextEndFrame(&g);

    SetCurrentViewport(NULL, NULL);

    // Drag and Drop: Elapse payload (if delivered, or if source stops being submitted)
    if (g.DragDropActive)
    {
        bool is_delivered = g.DragDropPayload.Delivery;
        bool is_elapsed = (g.DragDropPayload.DataFrameCount + 1 < g.FrameCount) && ((g.DragDropSourceFlags & ImGuiDragDropFlags_SourceAutoExpirePayload) || !IsMouseDown(g.DragDropMouseButton));
        if (is_delivered || is_elapsed)
            ClearDragDrop();
    }

    // Drag and Drop: Fallback for source tooltip. This is not ideal but better than nothing.
    if (g.DragDropActive && g.DragDropSourceFrameCount < g.FrameCount && !(g.DragDropSourceFlags & ImGuiDragDropFlags_SourceNoPreviewTooltip))
    {
        g.DragDropWithinSource = true;
        SetTooltip("...");
        g.DragDropWithinSource = false;
    }

    // End frame
    g.WithinFrameScope = false;
    g.FrameCountEnded = g.FrameCount;

    // Initiate moving window + handle left-click and right-click focus
    UpdateMouseMovingWindowEndFrame();

    // Update user-facing viewport list (g.Viewports -> g.PlatformIO.Viewports after filtering out some)
    UpdateViewportsEndFrame();

    // Sort the window list so that all child windows are after their parent
    // We cannot do that on FocusWindow() because children may not exist yet
    g.WindowsTempSortBuffer.resize(0);
    g.WindowsTempSortBuffer.reserve(g.Windows.Size);
    for (ImGuiWindow* window : g.Windows)
    {
        if (window->Active && (window->Flags & ImGuiWindowFlags_ChildWindow))       // if a child is active its parent will add it
            continue;
        AddWindowToSortBuffer(&g.WindowsTempSortBuffer, window);
    }

    // This usually assert if there is a mismatch between the ImGuiWindowFlags_ChildWindow / ParentWindow values and DC.ChildWindows[] in parents, aka we've done something wrong.
    IM_ASSERT(g.Windows.Size == g.WindowsTempSortBuffer.Size);
    g.Windows.swap(g.WindowsTempSortBuffer);
    g.IO.MetricsActiveWindows = g.WindowsActiveCount;

    // Unlock font atlas
    g.IO.Fonts->Locked = false;

    // Clear Input data for next frame
    g.IO.MousePosPrev = g.IO.MousePos;
    g.IO.AppFocusLost = false;
    g.IO.MouseWheel = g.IO.MouseWheelH = 0.0f;
    g.IO.InputQueueCharacters.resize(0);

    CallContextHooks(&g, ImGuiContextHookType_EndFramePost);
}

// Prepare the data for rendering so you can call GetDrawData()
// (As with anything within the ImGui:: namspace this doesn't touch your GPU or graphics API at all:
// it is the role of the ImGui_ImplXXXX_RenderDrawData() function provided by the renderer backend)
void ImGui::Render()
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(g.Initialized);

    if (g.FrameCountEnded != g.FrameCount)
        EndFrame();
    if (g.FrameCountRendered == g.FrameCount)
        return;
    g.FrameCountRendered = g.FrameCount;

    g.IO.MetricsRenderWindows = 0;
    CallContextHooks(&g, ImGuiContextHookType_RenderPre);

    // Add background ImDrawList (for each active viewport)
    for (ImGuiViewportP* viewport : g.Viewports)
    {
        InitViewportDrawData(viewport);
        if (viewport->BgFgDrawLists[0] != NULL)
            AddDrawListToDrawDataEx(&viewport->DrawDataP, viewport->DrawDataBuilder.Layers[0], GetBackgroundDrawList(viewport));
    }

    // Draw modal/window whitening backgrounds
    RenderDimmedBackgrounds();

    // Add ImDrawList to render
    ImGuiWindow* windows_to_render_top_most[2];
    windows_to_render_top_most[0] = (g.NavWindowingTarget && !(g.NavWindowingTarget->Flags & ImGuiWindowFlags_NoBringToFrontOnFocus)) ? g.NavWindowingTarget->RootWindowDockTree : NULL;
    windows_to_render_top_most[1] = (g.NavWindowingTarget ? g.NavWindowingListWindow : NULL);
    for (ImGuiWindow* window : g.Windows)
    {
        IM_MSVC_WARNING_SUPPRESS(6011); // Static Analysis false positive "warning C6011: Dereferencing NULL pointer 'window'"
        if (IsWindowActiveAndVisible(window) && (window->Flags & ImGuiWindowFlags_ChildWindow) == 0 && window != windows_to_render_top_most[0] && window != windows_to_render_top_most[1])
            AddRootWindowToDrawData(window);
    }
    for (int n = 0; n < IM_ARRAYSIZE(windows_to_render_top_most); n++)
        if (windows_to_render_top_most[n] && IsWindowActiveAndVisible(windows_to_render_top_most[n])) // NavWindowingTarget is always temporarily displayed as the top-most window
            AddRootWindowToDrawData(windows_to_render_top_most[n]);

    // Draw software mouse cursor if requested by io.MouseDrawCursor flag
    if (g.IO.MouseDrawCursor && g.MouseCursor != ImGuiMouseCursor_None)
        RenderMouseCursor(g.IO.MousePos, g.Style.MouseCursorScale, g.MouseCursor, IM_COL32_WHITE, IM_COL32_BLACK, IM_COL32(0, 0, 0, 48));

    // Setup ImDrawData structures for end-user
    g.IO.MetricsRenderVertices = g.IO.MetricsRenderIndices = 0;
    for (ImGuiViewportP* viewport : g.Viewports)
    {
        FlattenDrawDataIntoSingleLayer(&viewport->DrawDataBuilder);

        // Add foreground ImDrawList (for each active viewport)
        if (viewport->BgFgDrawLists[1] != NULL)
            AddDrawListToDrawDataEx(&viewport->DrawDataP, viewport->DrawDataBuilder.Layers[0], GetForegroundDrawList(viewport));

        // We call _PopUnusedDrawCmd() last thing, as RenderDimmedBackgrounds() rely on a valid command being there (especially in docking branch).
        ImDrawData* draw_data = &viewport->DrawDataP;
        IM_ASSERT(draw_data->CmdLists.Size == draw_data->CmdListsCount);
        for (ImDrawList* draw_list : draw_data->CmdLists)
            draw_list->_PopUnusedDrawCmd();

        g.IO.MetricsRenderVertices += draw_data->TotalVtxCount;
        g.IO.MetricsRenderIndices += draw_data->TotalIdxCount;
    }

    CallContextHooks(&g, ImGuiContextHookType_RenderPost);
}

// Calculate text size. Text can be multi-line. Optionally ignore text after a ## marker.
// CalcTextSize("") should return ImVec2(0.0f, g.FontSize)
ImVec2 ImGui::CalcTextSize(const char* text, const char* text_end, bool hide_text_after_double_hash, float wrap_width)
{
    ImGuiContext& g = *GImGui;

    const char* text_display_end;
    if (hide_text_after_double_hash)
        text_display_end = FindRenderedTextEnd(text, text_end);      // Hide anything after a '##' string
    else
        text_display_end = text_end;

    ImFont* font = g.Font;
    const float font_size = g.FontSize;
    if (text == text_display_end)
        return ImVec2(0.0f, font_size);
    ImVec2 text_size = font->CalcTextSizeA(font_size, FLT_MAX, wrap_width, text, text_display_end, NULL);

    // Round
    // FIXME: This has been here since Dec 2015 (7b0bf230) but down the line we want this out.
    // FIXME: Investigate using ceilf or e.g.
    // - https://git.musl-libc.org/cgit/musl/tree/src/math/ceilf.c
    // - https://embarkstudios.github.io/rust-gpu/api/src/libm/math/ceilf.rs.html
    text_size.x = IM_TRUNC(text_size.x + 0.99999f);

    return text_size;
}

// Find window given position, search front-to-back
// FIXME: Note that we have an inconsequential lag here: OuterRectClipped is updated in Begin(), so windows moved programmatically
// with SetWindowPos() and not SetNextWindowPos() will have that rectangle lagging by a frame at the time FindHoveredWindow() is
// called, aka before the next Begin(). Moving window isn't affected.
static void FindHoveredWindow()
{
    ImGuiContext& g = *GImGui;

    // Special handling for the window being moved: Ignore the mouse viewport check (because it may reset/lose its viewport during the undocking frame)
    ImGuiViewportP* moving_window_viewport = g.MovingWindow ? g.MovingWindow->Viewport : NULL;
    if (g.MovingWindow)
        g.MovingWindow->Viewport = g.MouseViewport;

    ImGuiWindow* hovered_window = NULL;
    ImGuiWindow* hovered_window_ignoring_moving_window = NULL;
    if (g.MovingWindow && !(g.MovingWindow->Flags & ImGuiWindowFlags_NoMouseInputs))
        hovered_window = g.MovingWindow;

    ImVec2 padding_regular = g.Style.TouchExtraPadding;
    ImVec2 padding_for_resize = g.IO.ConfigWindowsResizeFromEdges ? g.WindowsHoverPadding : padding_regular;
    for (int i = g.Windows.Size - 1; i >= 0; i--)
    {
        ImGuiWindow* window = g.Windows[i];
        IM_MSVC_WARNING_SUPPRESS(28182); // [Static Analyzer] Dereferencing NULL pointer.
        if (!window->Active || window->Hidden)
            continue;
        if (window->Flags & ImGuiWindowFlags_NoMouseInputs)
            continue;
        IM_ASSERT(window->Viewport);
        if (window->Viewport != g.MouseViewport)
            continue;

        // Using the clipped AABB, a child window will typically be clipped by its parent (not always)
        ImVec2 hit_padding = (window->Flags & (ImGuiWindowFlags_NoResize | ImGuiWindowFlags_AlwaysAutoResize)) ? padding_regular : padding_for_resize;
        if (!window->OuterRectClipped.ContainsWithPad(g.IO.MousePos, hit_padding))
            continue;

        // Support for one rectangular hole in any given window
        // FIXME: Consider generalizing hit-testing override (with more generic data, callback, etc.) (#1512)
        if (window->HitTestHoleSize.x != 0)
        {
            ImVec2 hole_pos(window->Pos.x + (float)window->HitTestHoleOffset.x, window->Pos.y + (float)window->HitTestHoleOffset.y);
            ImVec2 hole_size((float)window->HitTestHoleSize.x, (float)window->HitTestHoleSize.y);
            if (ImRect(hole_pos, hole_pos + hole_size).Contains(g.IO.MousePos))
                continue;
        }

        if (hovered_window == NULL)
            hovered_window = window;
        IM_MSVC_WARNING_SUPPRESS(28182); // [Static Analyzer] Dereferencing NULL pointer.
        if (hovered_window_ignoring_moving_window == NULL && (!g.MovingWindow || window->RootWindowDockTree != g.MovingWindow->RootWindowDockTree))
            hovered_window_ignoring_moving_window = window;
        if (hovered_window && hovered_window_ignoring_moving_window)
            break;
    }

    g.HoveredWindow = hovered_window;
    g.HoveredWindowUnderMovingWindow = hovered_window_ignoring_moving_window;

    if (g.MovingWindow)
        g.MovingWindow->Viewport = moving_window_viewport;
}

bool ImGui::IsItemActive()
{
    ImGuiContext& g = *GImGui;
    if (g.ActiveId)
        return g.ActiveId == g.LastItemData.ID;
    return false;
}

bool ImGui::IsItemActivated()
{
    ImGuiContext& g = *GImGui;
    if (g.ActiveId)
        if (g.ActiveId == g.LastItemData.ID && g.ActiveIdPreviousFrame != g.LastItemData.ID)
            return true;
    return false;
}

bool ImGui::IsItemDeactivated()
{
    ImGuiContext& g = *GImGui;
    if (g.LastItemData.StatusFlags & ImGuiItemStatusFlags_HasDeactivated)
        return (g.LastItemData.StatusFlags & ImGuiItemStatusFlags_Deactivated) != 0;
    return (g.ActiveIdPreviousFrame == g.LastItemData.ID && g.ActiveIdPreviousFrame != 0 && g.ActiveId != g.LastItemData.ID);
}

bool ImGui::IsItemDeactivatedAfterEdit()
{
    ImGuiContext& g = *GImGui;
    return IsItemDeactivated() && (g.ActiveIdPreviousFrameHasBeenEditedBefore || (g.ActiveId == 0 && g.ActiveIdHasBeenEditedBefore));
}

// == GetItemID() == GetFocusID()
bool ImGui::IsItemFocused()
{
    ImGuiContext& g = *GImGui;
    if (g.NavId != g.LastItemData.ID || g.NavId == 0)
        return false;

    // Special handling for the dummy item after Begin() which represent the title bar or tab.
    // When the window is collapsed (SkipItems==true) that last item will never be overwritten so we need to detect the case.
    ImGuiWindow* window = g.CurrentWindow;
    if (g.LastItemData.ID == window->ID && window->WriteAccessed)
        return false;

    return true;
}

// Important: this can be useful but it is NOT equivalent to the behavior of e.g.Button()!
// Most widgets have specific reactions based on mouse-up/down state, mouse position etc.
bool ImGui::IsItemClicked(ImGuiMouseButton mouse_button)
{
    return IsMouseClicked(mouse_button) && IsItemHovered(ImGuiHoveredFlags_None);
}

bool ImGui::IsItemToggledOpen()
{
    ImGuiContext& g = *GImGui;
    return (g.LastItemData.StatusFlags & ImGuiItemStatusFlags_ToggledOpen) ? true : false;
}

bool ImGui::IsItemToggledSelection()
{
    ImGuiContext& g = *GImGui;
    return (g.LastItemData.StatusFlags & ImGuiItemStatusFlags_ToggledSelection) ? true : false;
}

bool ImGui::IsAnyItemHovered()
{
    ImGuiContext& g = *GImGui;
    return g.HoveredId != 0 || g.HoveredIdPreviousFrame != 0;
}

bool ImGui::IsAnyItemActive()
{
    ImGuiContext& g = *GImGui;
    return g.ActiveId != 0;
}

bool ImGui::IsAnyItemFocused()
{
    ImGuiContext& g = *GImGui;
    return g.NavId != 0 && !g.NavDisableHighlight;
}

bool ImGui::IsItemVisible()
{
    ImGuiContext& g = *GImGui;
    return (g.LastItemData.StatusFlags & ImGuiItemStatusFlags_Visible) != 0;
}

bool ImGui::IsItemEdited()
{
    ImGuiContext& g = *GImGui;
    return (g.LastItemData.StatusFlags & ImGuiItemStatusFlags_Edited) != 0;
}

// Allow next item to be overlapped by subsequent items.
// This works by requiring HoveredId to match for two subsequent frames,
// so if a following items overwrite it our interactions will naturally be disabled.
void ImGui::SetNextItemAllowOverlap()
{
    ImGuiContext& g = *GImGui;
    g.NextItemData.ItemFlags |= ImGuiItemFlags_AllowOverlap;
}

#ifndef IMGUI_DISABLE_OBSOLETE_FUNCTIONS
// Allow last item to be overlapped by a subsequent item. Both may be activated during the same frame before the later one takes priority.
// FIXME-LEGACY: Use SetNextItemAllowOverlap() *before* your item instead.
void ImGui::SetItemAllowOverlap()
{
    ImGuiContext& g = *GImGui;
    ImGuiID id = g.LastItemData.ID;
    if (g.HoveredId == id)
        g.HoveredIdAllowOverlap = true;
    if (g.ActiveId == id) // Before we made this obsolete, most calls to SetItemAllowOverlap() used to avoid this path by testing g.ActiveId != id.
        g.ActiveIdAllowOverlap = true;
}
#endif

// FIXME: It might be undesirable that this will likely disable KeyOwner-aware shortcuts systems. Consider a more fine-tuned version for the two users of this function.
void ImGui::SetActiveIdUsingAllKeyboardKeys()
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(g.ActiveId != 0);
    g.ActiveIdUsingNavDirMask = (1 << ImGuiDir_COUNT) - 1;
    g.ActiveIdUsingAllKeyboardKeys = true;
    NavMoveRequestCancel();
}

ImGuiID ImGui::GetItemID()
{
    ImGuiContext& g = *GImGui;
    return g.LastItemData.ID;
}

ImVec2 ImGui::GetItemRectMin()
{
    ImGuiContext& g = *GImGui;
    return g.LastItemData.Rect.Min;
}

ImVec2 ImGui::GetItemRectMax()
{
    ImGuiContext& g = *GImGui;
    return g.LastItemData.Rect.Max;
}

ImVec2 ImGui::GetItemRectSize()
{
    ImGuiContext& g = *GImGui;
    return g.LastItemData.Rect.GetSize();
}

// Prior to v1.90 2023/10/16, the BeginChild() function took a 'bool border = false' parameter instead of 'ImGuiChildFlags child_flags = 0'.
// ImGuiChildFlags_Border is defined as always == 1 in order to allow old code passing 'true'.
bool ImGui::BeginChild(const char* str_id, const ImVec2& size_arg, ImGuiChildFlags child_flags, ImGuiWindowFlags window_flags)
{
    ImGuiID id = GetCurrentWindow()->GetID(str_id);
    return BeginChildEx(str_id, id, size_arg, child_flags, window_flags);
}

bool ImGui::BeginChild(ImGuiID id, const ImVec2& size_arg, ImGuiChildFlags child_flags, ImGuiWindowFlags window_flags)
{
    return BeginChildEx(NULL, id, size_arg, child_flags, window_flags);
}

bool ImGui::BeginChildEx(const char* name, ImGuiID id, const ImVec2& size_arg, ImGuiChildFlags child_flags, ImGuiWindowFlags window_flags)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* parent_window = g.CurrentWindow;
    IM_ASSERT(id != 0);

    // Sanity check as it is likely that some user will accidentally pass ImGuiWindowFlags into the ImGuiChildFlags argument.
    const ImGuiChildFlags ImGuiChildFlags_SupportedMask_ = ImGuiChildFlags_Border | ImGuiChildFlags_AlwaysUseWindowPadding | ImGuiChildFlags_ResizeX | ImGuiChildFlags_ResizeY | ImGuiChildFlags_AutoResizeX | ImGuiChildFlags_AutoResizeY | ImGuiChildFlags_AlwaysAutoResize | ImGuiChildFlags_FrameStyle;
    IM_UNUSED(ImGuiChildFlags_SupportedMask_);
    IM_ASSERT((child_flags & ~ImGuiChildFlags_SupportedMask_) == 0 && "Illegal ImGuiChildFlags value. Did you pass ImGuiWindowFlags values instead of ImGuiChildFlags?");
    IM_ASSERT((window_flags & ImGuiWindowFlags_AlwaysAutoResize) == 0 && "Cannot specify ImGuiWindowFlags_AlwaysAutoResize for BeginChild(). Use ImGuiChildFlags_AlwaysAutoResize!");
    if (child_flags & ImGuiChildFlags_AlwaysAutoResize)
    {
        IM_ASSERT((child_flags & (ImGuiChildFlags_ResizeX | ImGuiChildFlags_ResizeY)) == 0 && "Cannot use ImGuiChildFlags_ResizeX or ImGuiChildFlags_ResizeY with ImGuiChildFlags_AlwaysAutoResize!");
        IM_ASSERT((child_flags & (ImGuiChildFlags_AutoResizeX | ImGuiChildFlags_AutoResizeY)) != 0 && "Must use ImGuiChildFlags_AutoResizeX or ImGuiChildFlags_AutoResizeY with ImGuiChildFlags_AlwaysAutoResize!");
    }
#ifndef IMGUI_DISABLE_OBSOLETE_FUNCTIONS
    if (window_flags & ImGuiWindowFlags_AlwaysUseWindowPadding)
        child_flags |= ImGuiChildFlags_AlwaysUseWindowPadding;
#endif
    if (child_flags & ImGuiChildFlags_AutoResizeX)
        child_flags &= ~ImGuiChildFlags_ResizeX;
    if (child_flags & ImGuiChildFlags_AutoResizeY)
        child_flags &= ~ImGuiChildFlags_ResizeY;

    // Set window flags
    window_flags |= ImGuiWindowFlags_ChildWindow | ImGuiWindowFlags_NoTitleBar | ImGuiWindowFlags_NoDocking;
    window_flags |= (parent_window->Flags & ImGuiWindowFlags_NoMove); // Inherit the NoMove flag
    if (child_flags & (ImGuiChildFlags_AutoResizeX | ImGuiChildFlags_AutoResizeY | ImGuiChildFlags_AlwaysAutoResize))
        window_flags |= ImGuiWindowFlags_AlwaysAutoResize;
    if ((child_flags & (ImGuiChildFlags_ResizeX | ImGuiChildFlags_ResizeY)) == 0)
        window_flags |= ImGuiWindowFlags_NoResize | ImGuiWindowFlags_NoSavedSettings;

    // Special framed style
    if (child_flags & ImGuiChildFlags_FrameStyle)
    {
        PushStyleColor(ImGuiCol_ChildBg, g.Style.Colors[ImGuiCol_FrameBg]);
        PushStyleVar(ImGuiStyleVar_ChildRounding, g.Style.FrameRounding);
        PushStyleVar(ImGuiStyleVar_ChildBorderSize, g.Style.FrameBorderSize);
        PushStyleVar(ImGuiStyleVar_WindowPadding, g.Style.FramePadding);
        child_flags |= ImGuiChildFlags_Border | ImGuiChildFlags_AlwaysUseWindowPadding;
        window_flags |= ImGuiWindowFlags_NoMove;
    }

    // Forward child flags
    g.NextWindowData.Flags |= ImGuiNextWindowDataFlags_HasChildFlags;
    g.NextWindowData.ChildFlags = child_flags;

    // Forward size
    // Important: Begin() has special processing to switch condition to ImGuiCond_FirstUseEver for a given axis when ImGuiChildFlags_ResizeXXX is set.
    // (the alternative would to store conditional flags per axis, which is possible but more code)
    const ImVec2 size_avail = GetContentRegionAvail();
    const ImVec2 size_default((child_flags & ImGuiChildFlags_AutoResizeX) ? 0.0f : size_avail.x, (child_flags & ImGuiChildFlags_AutoResizeY) ? 0.0f : size_avail.y);
    const ImVec2 size = CalcItemSize(size_arg, size_default.x, size_default.y);
    SetNextWindowSize(size);

    // Build up name. If you need to append to a same child from multiple location in the ID stack, use BeginChild(ImGuiID id) with a stable value.
    const char* temp_window_name;
    if (name && parent_window->IDStack.back() == parent_window->ID)
        ImFormatStringToTempBuffer(&temp_window_name, NULL, "%s/%s", parent_window->Name, name); // May omit ID if in root of ID stack
    else if (name)
        ImFormatStringToTempBuffer(&temp_window_name, NULL, "%s/%s_%08X", parent_window->Name, name, id);
    else
        ImFormatStringToTempBuffer(&temp_window_name, NULL, "%s/%08X", parent_window->Name, id);

    // Set style
    const float backup_border_size = g.Style.ChildBorderSize;
    if ((child_flags & ImGuiChildFlags_Border) == 0)
        g.Style.ChildBorderSize = 0.0f;

    // Begin into window
    const bool ret = Begin(temp_window_name, NULL, window_flags);

    // Restore style
    g.Style.ChildBorderSize = backup_border_size;
    if (child_flags & ImGuiChildFlags_FrameStyle)
    {
        PopStyleVar(3);
        PopStyleColor();
    }

    ImGuiWindow* child_window = g.CurrentWindow;
    child_window->ChildId = id;

    // Set the cursor to handle case where the user called SetNextWindowPos()+BeginChild() manually.
    // While this is not really documented/defined, it seems that the expected thing to do.
    if (child_window->BeginCount == 1)
        parent_window->DC.CursorPos = child_window->Pos;

    // Process navigation-in immediately so NavInit can run on first frame
    // Can enter a child if (A) it has navigable items or (B) it can be scrolled.
    const ImGuiID temp_id_for_activation = ImHashStr("##Child", 0, id);
    if (g.ActiveId == temp_id_for_activation)
        ClearActiveID();
    if (g.NavActivateId == id && !(window_flags & ImGuiWindowFlags_NavFlattened) && (child_window->DC.NavLayersActiveMask != 0 || child_window->DC.NavWindowHasScrollY))
    {
        FocusWindow(child_window);
        NavInitWindow(child_window, false);
        SetActiveID(temp_id_for_activation, child_window); // Steal ActiveId with another arbitrary id so that key-press won't activate child item
        g.ActiveIdSource = g.NavInputSource;
    }
    return ret;
}

void ImGui::EndChild()
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* child_window = g.CurrentWindow;

    IM_ASSERT(g.WithinEndChild == false);
    IM_ASSERT(child_window->Flags & ImGuiWindowFlags_ChildWindow);   // Mismatched BeginChild()/EndChild() calls

    g.WithinEndChild = true;
    ImVec2 child_size = child_window->Size;
    End();
    if (child_window->BeginCount == 1)
    {
        ImGuiWindow* parent_window = g.CurrentWindow;
        ImRect bb(parent_window->DC.CursorPos, parent_window->DC.CursorPos + child_size);
        ItemSize(child_size);
        if ((child_window->DC.NavLayersActiveMask != 0 || child_window->DC.NavWindowHasScrollY) && !(child_window->Flags & ImGuiWindowFlags_NavFlattened))
        {
            ItemAdd(bb, child_window->ChildId);
            RenderNavHighlight(bb, child_window->ChildId);

            // When browsing a window that has no activable items (scroll only) we keep a highlight on the child (pass g.NavId to trick into always displaying)
            if (child_window->DC.NavLayersActiveMask == 0 && child_window == g.NavWindow)
                RenderNavHighlight(ImRect(bb.Min - ImVec2(2, 2), bb.Max + ImVec2(2, 2)), g.NavId, ImGuiNavHighlightFlags_TypeThin);
        }
        else
        {
            // Not navigable into
            ItemAdd(bb, 0);

            // But when flattened we directly reach items, adjust active layer mask accordingly
            if (child_window->Flags & ImGuiWindowFlags_NavFlattened)
                parent_window->DC.NavLayersActiveMaskNext |= child_window->DC.NavLayersActiveMaskNext;
        }
        if (g.HoveredWindow == child_window)
            g.LastItemData.StatusFlags |= ImGuiItemStatusFlags_HoveredWindow;
    }
    g.WithinEndChild = false;
    g.LogLinePosY = -FLT_MAX; // To enforce a carriage return
}

static void SetWindowConditionAllowFlags(ImGuiWindow* window, ImGuiCond flags, bool enabled)
{
    window->SetWindowPosAllowFlags       = enabled ? (window->SetWindowPosAllowFlags       | flags) : (window->SetWindowPosAllowFlags       & ~flags);
    window->SetWindowSizeAllowFlags      = enabled ? (window->SetWindowSizeAllowFlags      | flags) : (window->SetWindowSizeAllowFlags      & ~flags);
    window->SetWindowCollapsedAllowFlags = enabled ? (window->SetWindowCollapsedAllowFlags | flags) : (window->SetWindowCollapsedAllowFlags & ~flags);
    window->SetWindowDockAllowFlags      = enabled ? (window->SetWindowDockAllowFlags      | flags) : (window->SetWindowDockAllowFlags      & ~flags);
}

ImGuiWindow* ImGui::FindWindowByID(ImGuiID id)
{
    ImGuiContext& g = *GImGui;
    return (ImGuiWindow*)g.WindowsById.GetVoidPtr(id);
}

ImGuiWindow* ImGui::FindWindowByName(const char* name)
{
    ImGuiID id = ImHashStr(name);
    return FindWindowByID(id);
}

static void ApplyWindowSettings(ImGuiWindow* window, ImGuiWindowSettings* settings)
{
    const ImGuiViewport* main_viewport = ImGui::GetMainViewport();
    window->ViewportPos = main_viewport->Pos;
    if (settings->ViewportId)
    {
        window->ViewportId = settings->ViewportId;
        window->ViewportPos = ImVec2(settings->ViewportPos.x, settings->ViewportPos.y);
    }
    window->Pos = ImTrunc(ImVec2(settings->Pos.x + window->ViewportPos.x, settings->Pos.y + window->ViewportPos.y));
    if (settings->Size.x > 0 && settings->Size.y > 0)
        window->Size = window->SizeFull = ImTrunc(ImVec2(settings->Size.x, settings->Size.y));
    window->Collapsed = settings->Collapsed;
    window->DockId = settings->DockId;
    window->DockOrder = settings->DockOrder;
}

static void UpdateWindowInFocusOrderList(ImGuiWindow* window, bool just_created, ImGuiWindowFlags new_flags)
{
    ImGuiContext& g = *GImGui;

    const bool new_is_explicit_child = (new_flags & ImGuiWindowFlags_ChildWindow) != 0 && ((new_flags & ImGuiWindowFlags_Popup) == 0 || (new_flags & ImGuiWindowFlags_ChildMenu) != 0);
    const bool child_flag_changed = new_is_explicit_child != window->IsExplicitChild;
    if ((just_created || child_flag_changed) && !new_is_explicit_child)
    {
        IM_ASSERT(!g.WindowsFocusOrder.contains(window));
        g.WindowsFocusOrder.push_back(window);
        window->FocusOrder = (short)(g.WindowsFocusOrder.Size - 1);
    }
    else if (!just_created && child_flag_changed && new_is_explicit_child)
    {
        IM_ASSERT(g.WindowsFocusOrder[window->FocusOrder] == window);
        for (int n = window->FocusOrder + 1; n < g.WindowsFocusOrder.Size; n++)
            g.WindowsFocusOrder[n]->FocusOrder--;
        g.WindowsFocusOrder.erase(g.WindowsFocusOrder.Data + window->FocusOrder);
        window->FocusOrder = -1;
    }
    window->IsExplicitChild = new_is_explicit_child;
}

static void InitOrLoadWindowSettings(ImGuiWindow* window, ImGuiWindowSettings* settings)
{
    // Initial window state with e.g. default/arbitrary window position
    // Use SetNextWindowPos() with the appropriate condition flag to change the initial position of a window.
    const ImGuiViewport* main_viewport = ImGui::GetMainViewport();
    window->Pos = main_viewport->Pos + ImVec2(60, 60);
    window->Size = window->SizeFull = ImVec2(0, 0);
    window->ViewportPos = main_viewport->Pos;
    window->SetWindowPosAllowFlags = window->SetWindowSizeAllowFlags = window->SetWindowCollapsedAllowFlags = window->SetWindowDockAllowFlags = ImGuiCond_Always | ImGuiCond_Once | ImGuiCond_FirstUseEver | ImGuiCond_Appearing;

    if (settings != NULL)
    {
        SetWindowConditionAllowFlags(window, ImGuiCond_FirstUseEver, false);
        ApplyWindowSettings(window, settings);
    }
    window->DC.CursorStartPos = window->DC.CursorMaxPos = window->DC.IdealMaxPos = window->Pos; // So first call to CalcWindowContentSizes() doesn't return crazy values

    if ((window->Flags & ImGuiWindowFlags_AlwaysAutoResize) != 0)
    {
        window->AutoFitFramesX = window->AutoFitFramesY = 2;
        window->AutoFitOnlyGrows = false;
    }
    else
    {
        if (window->Size.x <= 0.0f)
            window->AutoFitFramesX = 2;
        if (window->Size.y <= 0.0f)
            window->AutoFitFramesY = 2;
        window->AutoFitOnlyGrows = (window->AutoFitFramesX > 0) || (window->AutoFitFramesY > 0);
    }
}

static ImGuiWindow* CreateNewWindow(const char* name, ImGuiWindowFlags flags)
{
    // Create window the first time
    //IMGUI_DEBUG_LOG("CreateNewWindow '%s', flags = 0x%08X\n", name, flags);
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = IM_NEW(ImGuiWindow)(&g, name);
    window->Flags = flags;
    g.WindowsById.SetVoidPtr(window->ID, window);

    ImGuiWindowSettings* settings = NULL;
    if (!(flags & ImGuiWindowFlags_NoSavedSettings))
        if ((settings = ImGui::FindWindowSettingsByWindow(window)) != 0)
            window->SettingsOffset = g.SettingsWindows.offset_from_ptr(settings);

    InitOrLoadWindowSettings(window, settings);

    if (flags & ImGuiWindowFlags_NoBringToFrontOnFocus)
        g.Windows.push_front(window); // Quite slow but rare and only once
    else
        g.Windows.push_back(window);

    return window;
}

static ImGuiWindow* GetWindowForTitleDisplay(ImGuiWindow* window)
{
    return window->DockNodeAsHost ? window->DockNodeAsHost->VisibleWindow : window;
}

static ImGuiWindow* GetWindowForTitleAndMenuHeight(ImGuiWindow* window)
{
    return (window->DockNodeAsHost && window->DockNodeAsHost->VisibleWindow) ? window->DockNodeAsHost->VisibleWindow : window;
}

static inline ImVec2 CalcWindowMinSize(ImGuiWindow* window)
{
    // Popups, menus and childs bypass style.WindowMinSize by default, but we give then a non-zero minimum size to facilitate understanding problematic cases (e.g. empty popups)
    ImGuiContext& g = *GImGui;
    ImVec2 size_min;
    if (window->Flags & (ImGuiWindowFlags_Popup | ImGuiWindowFlags_ChildMenu | ImGuiWindowFlags_ChildWindow))
    {
        size_min.x = (window->ChildFlags & ImGuiChildFlags_ResizeX) ? g.Style.WindowMinSize.x : 4.0f;
        size_min.y = (window->ChildFlags & ImGuiChildFlags_ResizeY) ? g.Style.WindowMinSize.y : 4.0f;
    }
    else
    {
        ImGuiWindow* window_for_height = GetWindowForTitleAndMenuHeight(window);
        size_min = g.Style.WindowMinSize;
        size_min.y = ImMax(size_min.y, window_for_height->TitleBarHeight() + window_for_height->MenuBarHeight() + ImMax(0.0f, g.Style.WindowRounding - 1.0f)); // Reduce artifacts with very small windows
    }
    return size_min;
}

static ImVec2 CalcWindowSizeAfterConstraint(ImGuiWindow* window, const ImVec2& size_desired)
{
    ImGuiContext& g = *GImGui;
    ImVec2 new_size = size_desired;
    if (g.NextWindowData.Flags & ImGuiNextWindowDataFlags_HasSizeConstraint)
    {
        // Using -1,-1 on either X/Y axis to preserve the current size.
        ImRect cr = g.NextWindowData.SizeConstraintRect;
        new_size.x = (cr.Min.x >= 0 && cr.Max.x >= 0) ? ImClamp(new_size.x, cr.Min.x, cr.Max.x) : window->SizeFull.x;
        new_size.y = (cr.Min.y >= 0 && cr.Max.y >= 0) ? ImClamp(new_size.y, cr.Min.y, cr.Max.y) : window->SizeFull.y;
        if (g.NextWindowData.SizeCallback)
        {
            ImGuiSizeCallbackData data;
            data.UserData = g.NextWindowData.SizeCallbackUserData;
            data.Pos = window->Pos;
            data.CurrentSize = window->SizeFull;
            data.DesiredSize = new_size;
            g.NextWindowData.SizeCallback(&data);
            new_size = data.DesiredSize;
        }
        new_size.x = IM_TRUNC(new_size.x);
        new_size.y = IM_TRUNC(new_size.y);
    }

    // Minimum size
    ImVec2 size_min = CalcWindowMinSize(window);
    return ImMax(new_size, size_min);
}

static void CalcWindowContentSizes(ImGuiWindow* window, ImVec2* content_size_current, ImVec2* content_size_ideal)
{
    bool preserve_old_content_sizes = false;
    if (window->Collapsed && window->AutoFitFramesX <= 0 && window->AutoFitFramesY <= 0)
        preserve_old_content_sizes = true;
    else if (window->Hidden && window->HiddenFramesCannotSkipItems == 0 && window->HiddenFramesCanSkipItems > 0)
        preserve_old_content_sizes = true;
    if (preserve_old_content_sizes)
    {
        *content_size_current = window->ContentSize;
        *content_size_ideal = window->ContentSizeIdeal;
        return;
    }

    content_size_current->x = (window->ContentSizeExplicit.x != 0.0f) ? window->ContentSizeExplicit.x : IM_TRUNC(window->DC.CursorMaxPos.x - window->DC.CursorStartPos.x);
    content_size_current->y = (window->ContentSizeExplicit.y != 0.0f) ? window->ContentSizeExplicit.y : IM_TRUNC(window->DC.CursorMaxPos.y - window->DC.CursorStartPos.y);
    content_size_ideal->x = (window->ContentSizeExplicit.x != 0.0f) ? window->ContentSizeExplicit.x : IM_TRUNC(ImMax(window->DC.CursorMaxPos.x, window->DC.IdealMaxPos.x) - window->DC.CursorStartPos.x);
    content_size_ideal->y = (window->ContentSizeExplicit.y != 0.0f) ? window->ContentSizeExplicit.y : IM_TRUNC(ImMax(window->DC.CursorMaxPos.y, window->DC.IdealMaxPos.y) - window->DC.CursorStartPos.y);
}

static ImVec2 CalcWindowAutoFitSize(ImGuiWindow* window, const ImVec2& size_contents)
{
    ImGuiContext& g = *GImGui;
    ImGuiStyle& style = g.Style;
    const float decoration_w_without_scrollbars = window->DecoOuterSizeX1 + window->DecoOuterSizeX2 - window->ScrollbarSizes.x;
    const float decoration_h_without_scrollbars = window->DecoOuterSizeY1 + window->DecoOuterSizeY2 - window->ScrollbarSizes.y;
    ImVec2 size_pad = window->WindowPadding * 2.0f;
    ImVec2 size_desired = size_contents + size_pad + ImVec2(decoration_w_without_scrollbars, decoration_h_without_scrollbars);
    if (window->Flags & ImGuiWindowFlags_Tooltip)
    {
        // Tooltip always resize
        return size_desired;
    }
    else
    {
        // Maximum window size is determined by the viewport size or monitor size
        ImVec2 size_min = CalcWindowMinSize(window);
        ImVec2 avail_size = window->Viewport->WorkSize;
        if (window->ViewportOwned)
            avail_size = ImVec2(FLT_MAX, FLT_MAX);
        const int monitor_idx = window->ViewportAllowPlatformMonitorExtend;
        if (monitor_idx >= 0 && monitor_idx < g.PlatformIO.Monitors.Size)
            avail_size = g.PlatformIO.Monitors[monitor_idx].WorkSize;
        ImVec2 size_auto_fit = ImClamp(size_desired, size_min, ImMax(size_min, avail_size - style.DisplaySafeAreaPadding * 2.0f));

        // When the window cannot fit all contents (either because of constraints, either because screen is too small),
        // we are growing the size on the other axis to compensate for expected scrollbar. FIXME: Might turn bigger than ViewportSize-WindowPadding.
        ImVec2 size_auto_fit_after_constraint = CalcWindowSizeAfterConstraint(window, size_auto_fit);
        bool will_have_scrollbar_x = (size_auto_fit_after_constraint.x - size_pad.x - decoration_w_without_scrollbars < size_contents.x  && !(window->Flags & ImGuiWindowFlags_NoScrollbar) && (window->Flags & ImGuiWindowFlags_HorizontalScrollbar)) || (window->Flags & ImGuiWindowFlags_AlwaysHorizontalScrollbar);
        bool will_have_scrollbar_y = (size_auto_fit_after_constraint.y - size_pad.y - decoration_h_without_scrollbars < size_contents.y && !(window->Flags & ImGuiWindowFlags_NoScrollbar)) || (window->Flags & ImGuiWindowFlags_AlwaysVerticalScrollbar);
        if (will_have_scrollbar_x)
            size_auto_fit.y += style.ScrollbarSize;
        if (will_have_scrollbar_y)
            size_auto_fit.x += style.ScrollbarSize;
        return size_auto_fit;
    }
}

ImVec2 ImGui::CalcWindowNextAutoFitSize(ImGuiWindow* window)
{
    ImVec2 size_contents_current;
    ImVec2 size_contents_ideal;
    CalcWindowContentSizes(window, &size_contents_current, &size_contents_ideal);
    ImVec2 size_auto_fit = CalcWindowAutoFitSize(window, size_contents_ideal);
    ImVec2 size_final = CalcWindowSizeAfterConstraint(window, size_auto_fit);
    return size_final;
}

static ImGuiCol GetWindowBgColorIdx(ImGuiWindow* window)
{
    if (window->Flags & (ImGuiWindowFlags_Tooltip | ImGuiWindowFlags_Popup))
        return ImGuiCol_PopupBg;
    if ((window->Flags & ImGuiWindowFlags_ChildWindow) && !window->DockIsActive)
        return ImGuiCol_ChildBg;
    return ImGuiCol_WindowBg;
}

static void CalcResizePosSizeFromAnyCorner(ImGuiWindow* window, const ImVec2& corner_target, const ImVec2& corner_norm, ImVec2* out_pos, ImVec2* out_size)
{
    ImVec2 pos_min = ImLerp(corner_target, window->Pos, corner_norm);                // Expected window upper-left
    ImVec2 pos_max = ImLerp(window->Pos + window->Size, corner_target, corner_norm); // Expected window lower-right
    ImVec2 size_expected = pos_max - pos_min;
    ImVec2 size_constrained = CalcWindowSizeAfterConstraint(window, size_expected);
    *out_pos = pos_min;
    if (corner_norm.x == 0.0f)
        out_pos->x -= (size_constrained.x - size_expected.x);
    if (corner_norm.y == 0.0f)
        out_pos->y -= (size_constrained.y - size_expected.y);
    *out_size = size_constrained;
}

// Data for resizing from resize grip / corner
struct ImGuiResizeGripDef
{
    ImVec2  CornerPosN;
    ImVec2  InnerDir;
    int     AngleMin12, AngleMax12;
};
static const ImGuiResizeGripDef resize_grip_def[4] =
{
    { ImVec2(1, 1), ImVec2(-1, -1), 0, 3 },  // Lower-right
    { ImVec2(0, 1), ImVec2(+1, -1), 3, 6 },  // Lower-left
    { ImVec2(0, 0), ImVec2(+1, +1), 6, 9 },  // Upper-left (Unused)
    { ImVec2(1, 0), ImVec2(-1, +1), 9, 12 }  // Upper-right (Unused)
};

// Data for resizing from borders
struct ImGuiResizeBorderDef
{
    ImVec2  InnerDir;               // Normal toward inside
    ImVec2  SegmentN1, SegmentN2;   // End positions, normalized (0,0: upper left)
    float   OuterAngle;             // Angle toward outside
};
static const ImGuiResizeBorderDef resize_border_def[4] =
{
    { ImVec2(+1, 0), ImVec2(0, 1), ImVec2(0, 0), IM_PI * 1.00f }, // Left
    { ImVec2(-1, 0), ImVec2(1, 0), ImVec2(1, 1), IM_PI * 0.00f }, // Right
    { ImVec2(0, +1), ImVec2(0, 0), ImVec2(1, 0), IM_PI * 1.50f }, // Up
    { ImVec2(0, -1), ImVec2(1, 1), ImVec2(0, 1), IM_PI * 0.50f }  // Down
};

static ImRect GetResizeBorderRect(ImGuiWindow* window, int border_n, float perp_padding, float thickness)
{
    ImRect rect = window->Rect();
    if (thickness == 0.0f)
        rect.Max -= ImVec2(1, 1);
    if (border_n == ImGuiDir_Left)  { return ImRect(rect.Min.x - thickness,    rect.Min.y + perp_padding, rect.Min.x + thickness,    rect.Max.y - perp_padding); }
    if (border_n == ImGuiDir_Right) { return ImRect(rect.Max.x - thickness,    rect.Min.y + perp_padding, rect.Max.x + thickness,    rect.Max.y - perp_padding); }
    if (border_n == ImGuiDir_Up)    { return ImRect(rect.Min.x + perp_padding, rect.Min.y - thickness,    rect.Max.x - perp_padding, rect.Min.y + thickness);    }
    if (border_n == ImGuiDir_Down)  { return ImRect(rect.Min.x + perp_padding, rect.Max.y - thickness,    rect.Max.x - perp_padding, rect.Max.y + thickness);    }
    IM_ASSERT(0);
    return ImRect();
}

// 0..3: corners (Lower-right, Lower-left, Unused, Unused)
ImGuiID ImGui::GetWindowResizeCornerID(ImGuiWindow* window, int n)
{
    IM_ASSERT(n >= 0 && n < 4);
    ImGuiID id = window->DockIsActive ? window->DockNode->HostWindow->ID : window->ID;
    id = ImHashStr("#RESIZE", 0, id);
    id = ImHashData(&n, sizeof(int), id);
    return id;
}

// Borders (Left, Right, Up, Down)
ImGuiID ImGui::GetWindowResizeBorderID(ImGuiWindow* window, ImGuiDir dir)
{
    IM_ASSERT(dir >= 0 && dir < 4);
    int n = (int)dir + 4;
    ImGuiID id = window->DockIsActive ? window->DockNode->HostWindow->ID : window->ID;
    id = ImHashStr("#RESIZE", 0, id);
    id = ImHashData(&n, sizeof(int), id);
    return id;
}

// Handle resize for: Resize Grips, Borders, Gamepad
// Return true when using auto-fit (double-click on resize grip)
static int ImGui::UpdateWindowManualResize(ImGuiWindow* window, const ImVec2& size_auto_fit, int* border_hovered, int* border_held, int resize_grip_count, ImU32 resize_grip_col[4], const ImRect& visibility_rect)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindowFlags flags = window->Flags;

    if ((flags & ImGuiWindowFlags_NoResize) || (flags & ImGuiWindowFlags_AlwaysAutoResize) || window->AutoFitFramesX > 0 || window->AutoFitFramesY > 0)
        return false;
    if (window->WasActive == false) // Early out to avoid running this code for e.g. a hidden implicit/fallback Debug window.
        return false;

    int ret_auto_fit_mask = 0x00;
    const float grip_draw_size = IM_TRUNC(ImMax(g.FontSize * 1.35f, window->WindowRounding + 1.0f + g.FontSize * 0.2f));
    const float grip_hover_inner_size = IM_TRUNC(grip_draw_size * 0.75f);
    const float grip_hover_outer_size = g.IO.ConfigWindowsResizeFromEdges ? WINDOWS_HOVER_PADDING : 0.0f;

    ImRect clamp_rect = visibility_rect;
    const bool window_move_from_title_bar = g.IO.ConfigWindowsMoveFromTitleBarOnly && !(window->Flags & ImGuiWindowFlags_NoTitleBar);
    if (window_move_from_title_bar)
        clamp_rect.Min.y -= window->TitleBarHeight();

    ImVec2 pos_target(FLT_MAX, FLT_MAX);
    ImVec2 size_target(FLT_MAX, FLT_MAX);

    // Clip mouse interaction rectangles within the viewport rectangle (in practice the narrowing is going to happen most of the time).
    // - Not narrowing would mostly benefit the situation where OS windows _without_ decoration have a threshold for hovering when outside their limits.
    //   This is however not the case with current backends under Win32, but a custom borderless window implementation would benefit from it.
    // - When decoration are enabled we typically benefit from that distance, but then our resize elements would be conflicting with OS resize elements, so we also narrow.
    // - Note that we are unable to tell if the platform setup allows hovering with a distance threshold (on Win32, decorated window have such threshold).
    // We only clip interaction so we overwrite window->ClipRect, cannot call PushClipRect() yet as DrawList is not yet setup.
    const bool clip_with_viewport_rect = !(g.IO.BackendFlags & ImGuiBackendFlags_HasMouseHoveredViewport) || (g.IO.MouseHoveredViewport != window->ViewportId) || !(window->Viewport->Flags & ImGuiViewportFlags_NoDecoration);
    if (clip_with_viewport_rect)
        window->ClipRect = window->Viewport->GetMainRect();

    // Resize grips and borders are on layer 1
    window->DC.NavLayerCurrent = ImGuiNavLayer_Menu;

    // Manual resize grips
    PushID("#RESIZE");
    for (int resize_grip_n = 0; resize_grip_n < resize_grip_count; resize_grip_n++)
    {
        const ImGuiResizeGripDef& def = resize_grip_def[resize_grip_n];
        const ImVec2 corner = ImLerp(window->Pos, window->Pos + window->Size, def.CornerPosN);

        // Using the FlattenChilds button flag we make the resize button accessible even if we are hovering over a child window
        bool hovered, held;
        ImRect resize_rect(corner - def.InnerDir * grip_hover_outer_size, corner + def.InnerDir * grip_hover_inner_size);
        if (resize_rect.Min.x > resize_rect.Max.x) ImSwap(resize_rect.Min.x, resize_rect.Max.x);
        if (resize_rect.Min.y > resize_rect.Max.y) ImSwap(resize_rect.Min.y, resize_rect.Max.y);
        ImGuiID resize_grip_id = window->GetID(resize_grip_n); // == GetWindowResizeCornerID()
        ItemAdd(resize_rect, resize_grip_id, NULL, ImGuiItemFlags_NoNav);
        ButtonBehavior(resize_rect, resize_grip_id, &hovered, &held, ImGuiButtonFlags_FlattenChildren | ImGuiButtonFlags_NoNavFocus);
        //GetForegroundDrawList(window)->AddRect(resize_rect.Min, resize_rect.Max, IM_COL32(255, 255, 0, 255));
        if (hovered || held)
            g.MouseCursor = (resize_grip_n & 1) ? ImGuiMouseCursor_ResizeNESW : ImGuiMouseCursor_ResizeNWSE;

        if (held && g.IO.MouseDoubleClicked[0])
        {
            // Auto-fit when double-clicking
            size_target = CalcWindowSizeAfterConstraint(window, size_auto_fit);
            ret_auto_fit_mask = 0x03; // Both axises
            ClearActiveID();
        }
        else if (held)
        {
            // Resize from any of the four corners
            // We don't use an incremental MouseDelta but rather compute an absolute target size based on mouse position
            ImVec2 clamp_min = ImVec2(def.CornerPosN.x == 1.0f ? clamp_rect.Min.x : -FLT_MAX, (def.CornerPosN.y == 1.0f || (def.CornerPosN.y == 0.0f && window_move_from_title_bar)) ? clamp_rect.Min.y : -FLT_MAX);
            ImVec2 clamp_max = ImVec2(def.CornerPosN.x == 0.0f ? clamp_rect.Max.x : +FLT_MAX, def.CornerPosN.y == 0.0f ? clamp_rect.Max.y : +FLT_MAX);
            ImVec2 corner_target = g.IO.MousePos - g.ActiveIdClickOffset + ImLerp(def.InnerDir * grip_hover_outer_size, def.InnerDir * -grip_hover_inner_size, def.CornerPosN); // Corner of the window corresponding to our corner grip
            corner_target = ImClamp(corner_target, clamp_min, clamp_max);
            CalcResizePosSizeFromAnyCorner(window, corner_target, def.CornerPosN, &pos_target, &size_target);
        }

        // Only lower-left grip is visible before hovering/activating
        if (resize_grip_n == 0 || held || hovered)
            resize_grip_col[resize_grip_n] = GetColorU32(held ? ImGuiCol_ResizeGripActive : hovered ? ImGuiCol_ResizeGripHovered : ImGuiCol_ResizeGrip);
    }

    int resize_border_mask = 0x00;
    if (window->Flags & ImGuiWindowFlags_ChildWindow)
        resize_border_mask |= ((window->ChildFlags & ImGuiChildFlags_ResizeX) ? 0x02 : 0) | ((window->ChildFlags & ImGuiChildFlags_ResizeY) ? 0x08 : 0);
    else
        resize_border_mask = g.IO.ConfigWindowsResizeFromEdges ? 0x0F : 0x00;
    for (int border_n = 0; border_n < 4; border_n++)
    {
        if ((resize_border_mask & (1 << border_n)) == 0)
            continue;
        const ImGuiResizeBorderDef& def = resize_border_def[border_n];
        const ImGuiAxis axis = (border_n == ImGuiDir_Left || border_n == ImGuiDir_Right) ? ImGuiAxis_X : ImGuiAxis_Y;

        bool hovered, held;
        ImRect border_rect = GetResizeBorderRect(window, border_n, grip_hover_inner_size, WINDOWS_HOVER_PADDING);
        ImGuiID border_id = window->GetID(border_n + 4); // == GetWindowResizeBorderID()
        ItemAdd(border_rect, border_id, NULL, ImGuiItemFlags_NoNav);
        ButtonBehavior(border_rect, border_id, &hovered, &held, ImGuiButtonFlags_FlattenChildren | ImGuiButtonFlags_NoNavFocus);
        //GetForegroundDrawList(window)->AddRect(border_rect.Min, border_rect.Max, IM_COL32(255, 255, 0, 255));
        if (hovered && g.HoveredIdTimer <= WINDOWS_RESIZE_FROM_EDGES_FEEDBACK_TIMER)
            hovered = false;
        if (hovered || held)
            g.MouseCursor = (axis == ImGuiAxis_X) ? ImGuiMouseCursor_ResizeEW : ImGuiMouseCursor_ResizeNS;
        if (held && g.IO.MouseDoubleClicked[0])
        {
            // Double-clicking bottom or right border auto-fit on this axis
            // FIXME: Support top and right borders: rework CalcResizePosSizeFromAnyCorner() to be reusable in both cases.
            if (border_n == 1 || border_n == 3) // Right and bottom border
            {
                size_target[axis] = CalcWindowSizeAfterConstraint(window, size_auto_fit)[axis];
                ret_auto_fit_mask |= (1 << axis);
                hovered = held = false; // So border doesn't show highlighted at new position
            }
            ClearActiveID();
        }
        else if (held)
        {
            // Switch to relative resizing mode when border geometry moved (e.g. resizing a child altering parent scroll), in order to avoid resizing feedback loop.
            // Currently only using relative mode on resizable child windows, as the problem to solve is more likely noticeable for them, but could apply for all windows eventually.
            // FIXME: May want to generalize this idiom at lower-level, so more widgets can use it!
            const bool just_scrolled_manually_while_resizing = (g.WheelingWindow != NULL && g.WheelingWindowScrolledFrame == g.FrameCount && IsWindowChildOf(window, g.WheelingWindow, false, true));
            if (g.ActiveIdIsJustActivated || just_scrolled_manually_while_resizing)
            {
                g.WindowResizeBorderExpectedRect = border_rect;
                g.WindowResizeRelativeMode = false;
            }
            if ((window->Flags & ImGuiWindowFlags_ChildWindow) && memcmp(&g.WindowResizeBorderExpectedRect, &border_rect, sizeof(ImRect)) != 0)
                g.WindowResizeRelativeMode = true;

            const ImVec2 border_curr = (window->Pos + ImMin(def.SegmentN1, def.SegmentN2) * window->Size);
            const float border_target_rel_mode_for_axis = border_curr[axis] + g.IO.MouseDelta[axis];
            const float border_target_abs_mode_for_axis = g.IO.MousePos[axis] - g.ActiveIdClickOffset[axis] + WINDOWS_HOVER_PADDING; // Match ButtonBehavior() padding above.

            // Use absolute mode position
            ImVec2 border_target = window->Pos;
            border_target[axis] = border_target_abs_mode_for_axis;

            // Use relative mode target for child window, ignore resize when moving back toward the ideal absolute position.
            bool ignore_resize = false;
            if (g.WindowResizeRelativeMode)
            {
                //GetForegroundDrawList()->AddText(GetMainViewport()->WorkPos, IM_COL32_WHITE, "Relative Mode");
                border_target[axis] = border_target_rel_mode_for_axis;
                if (g.IO.MouseDelta[axis] == 0.0f || (g.IO.MouseDelta[axis] > 0.0f) == (border_target_rel_mode_for_axis > border_target_abs_mode_for_axis))
                    ignore_resize = true;
            }

            // Clamp, apply
            ImVec2 clamp_min(border_n == ImGuiDir_Right ? clamp_rect.Min.x : -FLT_MAX, border_n == ImGuiDir_Down || (border_n == ImGuiDir_Up && window_move_from_title_bar) ? clamp_rect.Min.y : -FLT_MAX);
            ImVec2 clamp_max(border_n == ImGuiDir_Left ? clamp_rect.Max.x : +FLT_MAX, border_n == ImGuiDir_Up ? clamp_rect.Max.y : +FLT_MAX);
            border_target = ImClamp(border_target, clamp_min, clamp_max);
            if (flags & ImGuiWindowFlags_ChildWindow) // Clamp resizing of childs within parent
            {
                if ((flags & (ImGuiWindowFlags_HorizontalScrollbar | ImGuiWindowFlags_AlwaysHorizontalScrollbar)) == 0 || (flags & ImGuiWindowFlags_NoScrollbar))
                    border_target.x = ImClamp(border_target.x, window->ParentWindow->InnerClipRect.Min.x, window->ParentWindow->InnerClipRect.Max.x);
                if (flags & ImGuiWindowFlags_NoScrollbar)
                    border_target.y = ImClamp(border_target.y, window->ParentWindow->InnerClipRect.Min.y, window->ParentWindow->InnerClipRect.Max.y);
            }
            if (!ignore_resize)
                CalcResizePosSizeFromAnyCorner(window, border_target, ImMin(def.SegmentN1, def.SegmentN2), &pos_target, &size_target);
        }
        if (hovered)
            *border_hovered = border_n;
        if (held)
            *border_held = border_n;
    }
    PopID();

    // Restore nav layer
    window->DC.NavLayerCurrent = ImGuiNavLayer_Main;

    // Navigation resize (keyboard/gamepad)
    // FIXME: This cannot be moved to NavUpdateWindowing() because CalcWindowSizeAfterConstraint() need to callback into user.
    // Not even sure the callback works here.
    if (g.NavWindowingTarget && g.NavWindowingTarget->RootWindowDockTree == window)
    {
        ImVec2 nav_resize_dir;
        if (g.NavInputSource == ImGuiInputSource_Keyboard && g.IO.KeyShift)
            nav_resize_dir = GetKeyMagnitude2d(ImGuiKey_LeftArrow, ImGuiKey_RightArrow, ImGuiKey_UpArrow, ImGuiKey_DownArrow);
        if (g.NavInputSource == ImGuiInputSource_Gamepad)
            nav_resize_dir = GetKeyMagnitude2d(ImGuiKey_GamepadDpadLeft, ImGuiKey_GamepadDpadRight, ImGuiKey_GamepadDpadUp, ImGuiKey_GamepadDpadDown);
        if (nav_resize_dir.x != 0.0f || nav_resize_dir.y != 0.0f)
        {
            const float NAV_RESIZE_SPEED = 600.0f;
            const float resize_step = NAV_RESIZE_SPEED * g.IO.DeltaTime * ImMin(g.IO.DisplayFramebufferScale.x, g.IO.DisplayFramebufferScale.y);
            g.NavWindowingAccumDeltaSize += nav_resize_dir * resize_step;
            g.NavWindowingAccumDeltaSize = ImMax(g.NavWindowingAccumDeltaSize, clamp_rect.Min - window->Pos - window->Size); // We need Pos+Size >= clmap_rect.Min, so Size >= clmap_rect.Min - Pos, so size_delta >= clmap_rect.Min - window->Pos - window->Size
            g.NavWindowingToggleLayer = false;
            g.NavDisableMouseHover = true;
            resize_grip_col[0] = GetColorU32(ImGuiCol_ResizeGripActive);
            ImVec2 accum_floored = ImTrunc(g.NavWindowingAccumDeltaSize);
            if (accum_floored.x != 0.0f || accum_floored.y != 0.0f)
            {
                // FIXME-NAV: Should store and accumulate into a separate size buffer to handle sizing constraints properly, right now a constraint will make us stuck.
                size_target = CalcWindowSizeAfterConstraint(window, window->SizeFull + accum_floored);
                g.NavWindowingAccumDeltaSize -= accum_floored;
            }
        }
    }

    // Apply back modified position/size to window
    if (size_target.x != FLT_MAX)
        window->Size.x = window->SizeFull.x = size_target.x;
    if (size_target.y != FLT_MAX)
        window->Size.y = window->SizeFull.y = size_target.y;
    if (pos_target.x != FLT_MAX)
        window->Pos.x = ImTrunc(pos_target.x);
    if (pos_target.y != FLT_MAX)
        window->Pos.y = ImTrunc(pos_target.y);
    if (size_target.x != FLT_MAX || size_target.y != FLT_MAX || pos_target.x != FLT_MAX || pos_target.y != FLT_MAX)
        MarkIniSettingsDirty(window);

    // Recalculate next expected border expected coordinates
    if (*border_held != -1)
        g.WindowResizeBorderExpectedRect = GetResizeBorderRect(window, *border_held, grip_hover_inner_size, WINDOWS_HOVER_PADDING);

    return ret_auto_fit_mask;
}

static inline void ClampWindowPos(ImGuiWindow* window, const ImRect& visibility_rect)
{
    ImGuiContext& g = *GImGui;
    ImVec2 size_for_clamping = window->Size;
    if (g.IO.ConfigWindowsMoveFromTitleBarOnly && (!(window->Flags & ImGuiWindowFlags_NoTitleBar) || window->DockNodeAsHost))
        size_for_clamping.y = ImGui::GetFrameHeight(); // Not using window->TitleBarHeight() as DockNodeAsHost will report 0.0f here.
    window->Pos = ImClamp(window->Pos, visibility_rect.Min - size_for_clamping, visibility_rect.Max);
}

static void ImGui::RenderWindowOuterBorders(ImGuiWindow* window)
{
    ImGuiContext& g = *GImGui;
    float rounding = window->WindowRounding;
    float border_size = window->WindowBorderSize;
    if (border_size > 0.0f && !(window->Flags & ImGuiWindowFlags_NoBackground))
        window->DrawList->AddRect(window->Pos, window->Pos + window->Size, GetColorU32(ImGuiCol_Border), rounding, 0, border_size);

    if (window->ResizeBorderHovered != -1 || window->ResizeBorderHeld != -1)
    {
        const int border_n = (window->ResizeBorderHeld != -1) ? window->ResizeBorderHeld : window->ResizeBorderHovered;
        const ImGuiResizeBorderDef& def = resize_border_def[border_n];
        const ImRect border_r = GetResizeBorderRect(window, border_n, rounding, 0.0f);
        const ImU32 border_col = GetColorU32((window->ResizeBorderHeld != -1) ? ImGuiCol_SeparatorActive : ImGuiCol_SeparatorHovered);
        window->DrawList->PathArcTo(ImLerp(border_r.Min, border_r.Max, def.SegmentN1) + ImVec2(0.5f, 0.5f) + def.InnerDir * rounding, rounding, def.OuterAngle - IM_PI * 0.25f, def.OuterAngle);
        window->DrawList->PathArcTo(ImLerp(border_r.Min, border_r.Max, def.SegmentN2) + ImVec2(0.5f, 0.5f) + def.InnerDir * rounding, rounding, def.OuterAngle, def.OuterAngle + IM_PI * 0.25f);
        window->DrawList->PathStroke(border_col, 0, ImMax(2.0f, border_size)); // Thicker than usual
    }
    if (g.Style.FrameBorderSize > 0 && !(window->Flags & ImGuiWindowFlags_NoTitleBar) && !window->DockIsActive)
    {
        float y = window->Pos.y + window->TitleBarHeight() - 1;
        window->DrawList->AddLine(ImVec2(window->Pos.x + border_size, y), ImVec2(window->Pos.x + window->Size.x - border_size, y), GetColorU32(ImGuiCol_Border), g.Style.FrameBorderSize);
    }
}

// Draw background and borders
// Draw and handle scrollbars
void ImGui::RenderWindowDecorations(ImGuiWindow* window, const ImRect& title_bar_rect, bool title_bar_is_highlight, bool handle_borders_and_resize_grips, int resize_grip_count, const ImU32 resize_grip_col[4], float resize_grip_draw_size)
{
    ImGuiContext& g = *GImGui;
    ImGuiStyle& style = g.Style;
    ImGuiWindowFlags flags = window->Flags;

    // Ensure that ScrollBar doesn't read last frame's SkipItems
    IM_ASSERT(window->BeginCount == 0);
    window->SkipItems = false;

    // Draw window + handle manual resize
    // As we highlight the title bar when want_focus is set, multiple reappearing windows will have their title bar highlighted on their reappearing frame.
    const float window_rounding = window->WindowRounding;
    const float window_border_size = window->WindowBorderSize;
    if (window->Collapsed)
    {
        // Title bar only
        const float backup_border_size = style.FrameBorderSize;
        g.Style.FrameBorderSize = window->WindowBorderSize;
        ImU32 title_bar_col = GetColorU32((title_bar_is_highlight && !g.NavDisableHighlight) ? ImGuiCol_TitleBgActive : ImGuiCol_TitleBgCollapsed);
        if (window->ViewportOwned)
            title_bar_col |= IM_COL32_A_MASK; // No alpha (we don't support is_docking_transparent_payload here because simpler and less meaningful, but could with a bit of code shuffle/reuse)
        RenderFrame(title_bar_rect.Min, title_bar_rect.Max, title_bar_col, true, window_rounding);
        g.Style.FrameBorderSize = backup_border_size;
    }
    else
    {
        // Window background
        if (!(flags & ImGuiWindowFlags_NoBackground))
        {
            bool is_docking_transparent_payload = false;
            if (g.DragDropActive && (g.FrameCount - g.DragDropAcceptFrameCount) <= 1 && g.IO.ConfigDockingTransparentPayload)
                if (g.DragDropPayload.IsDataType(IMGUI_PAYLOAD_TYPE_WINDOW) && *(ImGuiWindow**)g.DragDropPayload.Data == window)
                    is_docking_transparent_payload = true;

            ImU32 bg_col = GetColorU32(GetWindowBgColorIdx(window));
            if (window->ViewportOwned)
            {
                bg_col |= IM_COL32_A_MASK; // No alpha
                if (is_docking_transparent_payload)
                    window->Viewport->Alpha *= DOCKING_TRANSPARENT_PAYLOAD_ALPHA;
            }
            else
            {
                // Adjust alpha. For docking
                bool override_alpha = false;
                float alpha = 1.0f;
                if (g.NextWindowData.Flags & ImGuiNextWindowDataFlags_HasBgAlpha)
                {
                    alpha = g.NextWindowData.BgAlphaVal;
                    override_alpha = true;
                }
                if (is_docking_transparent_payload)
                {
                    alpha *= DOCKING_TRANSPARENT_PAYLOAD_ALPHA; // FIXME-DOCK: Should that be an override?
                    override_alpha = true;
                }
                if (override_alpha)
                    bg_col = (bg_col & ~IM_COL32_A_MASK) | (IM_F32_TO_INT8_SAT(alpha) << IM_COL32_A_SHIFT);
            }

            // Render, for docked windows and host windows we ensure bg goes before decorations
            if (window->DockIsActive)
                window->DockNode->LastBgColor = bg_col;
            ImDrawList* bg_draw_list = window->DockIsActive ? window->DockNode->HostWindow->DrawList : window->DrawList;
            if (window->DockIsActive || (flags & ImGuiWindowFlags_DockNodeHost))
                bg_draw_list->ChannelsSetCurrent(DOCKING_HOST_DRAW_CHANNEL_BG);
            bg_draw_list->AddRectFilled(window->Pos + ImVec2(0, window->TitleBarHeight()), window->Pos + window->Size, bg_col, window_rounding, (flags & ImGuiWindowFlags_NoTitleBar) ? 0 : ImDrawFlags_RoundCornersBottom);
            if (window->DockIsActive || (flags & ImGuiWindowFlags_DockNodeHost))
                bg_draw_list->ChannelsSetCurrent(DOCKING_HOST_DRAW_CHANNEL_FG);
        }
        if (window->DockIsActive)
            window->DockNode->IsBgDrawnThisFrame = true;

        // Title bar
        // (when docked, DockNode are drawing their own title bar. Individual windows however do NOT set the _NoTitleBar flag,
        // in order for their pos/size to be matching their undocking state.)
        if (!(flags & ImGuiWindowFlags_NoTitleBar) && !window->DockIsActive)
        {
            ImU32 title_bar_col = GetColorU32(title_bar_is_highlight ? ImGuiCol_TitleBgActive : ImGuiCol_TitleBg);
            window->DrawList->AddRectFilled(title_bar_rect.Min, title_bar_rect.Max, title_bar_col, window_rounding, ImDrawFlags_RoundCornersTop);
        }

        // Menu bar
        if (flags & ImGuiWindowFlags_MenuBar)
        {
            ImRect menu_bar_rect = window->MenuBarRect();
            menu_bar_rect.ClipWith(window->Rect());  // Soft clipping, in particular child window don't have minimum size covering the menu bar so this is useful for them.
            window->DrawList->AddRectFilled(menu_bar_rect.Min + ImVec2(window_border_size, 0), menu_bar_rect.Max - ImVec2(window_border_size, 0), GetColorU32(ImGuiCol_MenuBarBg), (flags & ImGuiWindowFlags_NoTitleBar) ? window_rounding : 0.0f, ImDrawFlags_RoundCornersTop);
            if (style.FrameBorderSize > 0.0f && menu_bar_rect.Max.y < window->Pos.y + window->Size.y)
                window->DrawList->AddLine(menu_bar_rect.GetBL(), menu_bar_rect.GetBR(), GetColorU32(ImGuiCol_Border), style.FrameBorderSize);
        }

        // Docking: Unhide tab bar (small triangle in the corner), drag from small triangle to quickly undock
        ImGuiDockNode* node = window->DockNode;
        if (window->DockIsActive && node->IsHiddenTabBar() && !node->IsNoTabBar())
        {
            float unhide_sz_draw = ImTrunc(g.FontSize * 0.70f);
            float unhide_sz_hit = ImTrunc(g.FontSize * 0.55f);
            ImVec2 p = node->Pos;
            ImRect r(p, p + ImVec2(unhide_sz_hit, unhide_sz_hit));
            ImGuiID unhide_id = window->GetID("#UNHIDE");
            KeepAliveID(unhide_id);
            bool hovered, held;
            if (ButtonBehavior(r, unhide_id, &hovered, &held, ImGuiButtonFlags_FlattenChildren))
                node->WantHiddenTabBarToggle = true;
            else if (held && IsMouseDragging(0))
                StartMouseMovingWindowOrNode(window, node, true); // Undock from tab-bar triangle = same as window/collapse menu button

            // FIXME-DOCK: Ideally we'd use ImGuiCol_TitleBgActive/ImGuiCol_TitleBg here, but neither is guaranteed to be visible enough at this sort of size..
            ImU32 col = GetColorU32(((held && hovered) || (node->IsFocused && !hovered)) ? ImGuiCol_ButtonActive : hovered ? ImGuiCol_ButtonHovered : ImGuiCol_Button);
            window->DrawList->AddTriangleFilled(p, p + ImVec2(unhide_sz_draw, 0.0f), p + ImVec2(0.0f, unhide_sz_draw), col);
        }

        // Scrollbars
        if (window->ScrollbarX)
            Scrollbar(ImGuiAxis_X);
        if (window->ScrollbarY)
            Scrollbar(ImGuiAxis_Y);

        // Render resize grips (after their input handling so we don't have a frame of latency)
        if (handle_borders_and_resize_grips && !(flags & ImGuiWindowFlags_NoResize))
        {
            for (int resize_grip_n = 0; resize_grip_n < resize_grip_count; resize_grip_n++)
            {
                const ImU32 col = resize_grip_col[resize_grip_n];
                if ((col & IM_COL32_A_MASK) == 0)
                    continue;
                const ImGuiResizeGripDef& grip = resize_grip_def[resize_grip_n];
                const ImVec2 corner = ImLerp(window->Pos, window->Pos + window->Size, grip.CornerPosN);
                window->DrawList->PathLineTo(corner + grip.InnerDir * ((resize_grip_n & 1) ? ImVec2(window_border_size, resize_grip_draw_size) : ImVec2(resize_grip_draw_size, window_border_size)));
                window->DrawList->PathLineTo(corner + grip.InnerDir * ((resize_grip_n & 1) ? ImVec2(resize_grip_draw_size, window_border_size) : ImVec2(window_border_size, resize_grip_draw_size)));
                window->DrawList->PathArcToFast(ImVec2(corner.x + grip.InnerDir.x * (window_rounding + window_border_size), corner.y + grip.InnerDir.y * (window_rounding + window_border_size)), window_rounding, grip.AngleMin12, grip.AngleMax12);
                window->DrawList->PathFillConvex(col);
            }
        }

        // Borders (for dock node host they will be rendered over after the tab bar)
        if (handle_borders_and_resize_grips && !window->DockNodeAsHost)
            RenderWindowOuterBorders(window);
    }
}

// When inside a dock node, this is handled in DockNodeCalcTabBarLayout() instead.
// Render title text, collapse button, close button
void ImGui::RenderWindowTitleBarContents(ImGuiWindow* window, const ImRect& title_bar_rect, const char* name, bool* p_open)
{
    ImGuiContext& g = *GImGui;
    ImGuiStyle& style = g.Style;
    ImGuiWindowFlags flags = window->Flags;

    const bool has_close_button = (p_open != NULL);
    const bool has_collapse_button = !(flags & ImGuiWindowFlags_NoCollapse) && (style.WindowMenuButtonPosition != ImGuiDir_None);

    // Close & Collapse button are on the Menu NavLayer and don't default focus (unless there's nothing else on that layer)
    // FIXME-NAV: Might want (or not?) to set the equivalent of ImGuiButtonFlags_NoNavFocus so that mouse clicks on standard title bar items don't necessarily set nav/keyboard ref?
    const ImGuiItemFlags item_flags_backup = g.CurrentItemFlags;
    g.CurrentItemFlags |= ImGuiItemFlags_NoNavDefaultFocus;
    window->DC.NavLayerCurrent = ImGuiNavLayer_Menu;

    // Layout buttons
    // FIXME: Would be nice to generalize the subtleties expressed here into reusable code.
    float pad_l = style.FramePadding.x;
    float pad_r = style.FramePadding.x;
    float button_sz = g.FontSize;
    ImVec2 close_button_pos;
    ImVec2 collapse_button_pos;
    if (has_close_button)
    {
        close_button_pos = ImVec2(title_bar_rect.Max.x - pad_r - button_sz, title_bar_rect.Min.y + style.FramePadding.y);
        pad_r += button_sz + style.ItemInnerSpacing.x;
    }
    if (has_collapse_button && style.WindowMenuButtonPosition == ImGuiDir_Right)
    {
        collapse_button_pos = ImVec2(title_bar_rect.Max.x - pad_r - button_sz, title_bar_rect.Min.y + style.FramePadding.y);
        pad_r += button_sz + style.ItemInnerSpacing.x;
    }
    if (has_collapse_button && style.WindowMenuButtonPosition == ImGuiDir_Left)
    {
        collapse_button_pos = ImVec2(title_bar_rect.Min.x + pad_l, title_bar_rect.Min.y + style.FramePadding.y);
        pad_l += button_sz + style.ItemInnerSpacing.x;
    }

    // Collapse button (submitting first so it gets priority when choosing a navigation init fallback)
    if (has_collapse_button)
        if (CollapseButton(window->GetID("#COLLAPSE"), collapse_button_pos, NULL))
            window->WantCollapseToggle = true; // Defer actual collapsing to next frame as we are too far in the Begin() function

    // Close button
    if (has_close_button)
        if (CloseButton(window->GetID("#CLOSE"), close_button_pos))
            *p_open = false;

    window->DC.NavLayerCurrent = ImGuiNavLayer_Main;
    g.CurrentItemFlags = item_flags_backup;

    // Title bar text (with: horizontal alignment, avoiding collapse/close button, optional "unsaved document" marker)
    // FIXME: Refactor text alignment facilities along with RenderText helpers, this is WAY too much messy code..
    const float marker_size_x = (flags & ImGuiWindowFlags_UnsavedDocument) ? button_sz * 0.80f : 0.0f;
    const ImVec2 text_size = CalcTextSize(name, NULL, true) + ImVec2(marker_size_x, 0.0f);

    // As a nice touch we try to ensure that centered title text doesn't get affected by visibility of Close/Collapse button,
    // while uncentered title text will still reach edges correctly.
    if (pad_l > style.FramePadding.x)
        pad_l += g.Style.ItemInnerSpacing.x;
    if (pad_r > style.FramePadding.x)
        pad_r += g.Style.ItemInnerSpacing.x;
    if (style.WindowTitleAlign.x > 0.0f && style.WindowTitleAlign.x < 1.0f)
    {
        float centerness = ImSaturate(1.0f - ImFabs(style.WindowTitleAlign.x - 0.5f) * 2.0f); // 0.0f on either edges, 1.0f on center
        float pad_extend = ImMin(ImMax(pad_l, pad_r), title_bar_rect.GetWidth() - pad_l - pad_r - text_size.x);
        pad_l = ImMax(pad_l, pad_extend * centerness);
        pad_r = ImMax(pad_r, pad_extend * centerness);
    }

    ImRect layout_r(title_bar_rect.Min.x + pad_l, title_bar_rect.Min.y, title_bar_rect.Max.x - pad_r, title_bar_rect.Max.y);
    ImRect clip_r(layout_r.Min.x, layout_r.Min.y, ImMin(layout_r.Max.x + g.Style.ItemInnerSpacing.x, title_bar_rect.Max.x), layout_r.Max.y);
    if (flags & ImGuiWindowFlags_UnsavedDocument)
    {
        ImVec2 marker_pos;
        marker_pos.x = ImClamp(layout_r.Min.x + (layout_r.GetWidth() - text_size.x) * style.WindowTitleAlign.x + text_size.x, layout_r.Min.x, layout_r.Max.x);
        marker_pos.y = (layout_r.Min.y + layout_r.Max.y) * 0.5f;
        if (marker_pos.x > layout_r.Min.x)
        {
            RenderBullet(window->DrawList, marker_pos, GetColorU32(ImGuiCol_Text));
            clip_r.Max.x = ImMin(clip_r.Max.x, marker_pos.x - (int)(marker_size_x * 0.5f));
        }
    }
    //if (g.IO.KeyShift) window->DrawList->AddRect(layout_r.Min, layout_r.Max, IM_COL32(255, 128, 0, 255)); // [DEBUG]
    //if (g.IO.KeyCtrl) window->DrawList->AddRect(clip_r.Min, clip_r.Max, IM_COL32(255, 128, 0, 255)); // [DEBUG]
    RenderTextClipped(layout_r.Min, layout_r.Max, name, NULL, &text_size, style.WindowTitleAlign, &clip_r);
}

void ImGui::UpdateWindowParentAndRootLinks(ImGuiWindow* window, ImGuiWindowFlags flags, ImGuiWindow* parent_window)
{
    window->ParentWindow = parent_window;
    window->RootWindow = window->RootWindowPopupTree = window->RootWindowDockTree = window->RootWindowForTitleBarHighlight = window->RootWindowForNav = window;
    if (parent_window && (flags & ImGuiWindowFlags_ChildWindow) && !(flags & ImGuiWindowFlags_Tooltip))
    {
        window->RootWindowDockTree = parent_window->RootWindowDockTree;
        if (!window->DockIsActive && !(parent_window->Flags & ImGuiWindowFlags_DockNodeHost))
            window->RootWindow = parent_window->RootWindow;
    }
    if (parent_window && (flags & ImGuiWindowFlags_Popup))
        window->RootWindowPopupTree = parent_window->RootWindowPopupTree;
    if (parent_window && !(flags & ImGuiWindowFlags_Modal) && (flags & (ImGuiWindowFlags_ChildWindow | ImGuiWindowFlags_Popup))) // FIXME: simply use _NoTitleBar ?
        window->RootWindowForTitleBarHighlight = parent_window->RootWindowForTitleBarHighlight;
    while (window->RootWindowForNav->Flags & ImGuiWindowFlags_NavFlattened)
    {
        IM_ASSERT(window->RootWindowForNav->ParentWindow != NULL);
        window->RootWindowForNav = window->RootWindowForNav->ParentWindow;
    }
}

// When a modal popup is open, newly created windows that want focus (i.e. are not popups and do not specify ImGuiWindowFlags_NoFocusOnAppearing)
// should be positioned behind that modal window, unless the window was created inside the modal begin-stack.
// In case of multiple stacked modals newly created window honors begin stack order and does not go below its own modal parent.
// - WindowA            // FindBlockingModal() returns Modal1
//   - WindowB          //                  .. returns Modal1
//   - Modal1           //                  .. returns Modal2
//      - WindowC       //                  .. returns Modal2
//          - WindowD   //                  .. returns Modal2
//          - Modal2    //                  .. returns Modal2
//            - WindowE //                  .. returns NULL
// Notes:
// - FindBlockingModal(NULL) == NULL is generally equivalent to GetTopMostPopupModal() == NULL.
//   Only difference is here we check for ->Active/WasActive but it may be unecessary.
ImGuiWindow* ImGui::FindBlockingModal(ImGuiWindow* window)
{
    ImGuiContext& g = *GImGui;
    if (g.OpenPopupStack.Size <= 0)
        return NULL;

    // Find a modal that has common parent with specified window. Specified window should be positioned behind that modal.
    for (ImGuiPopupData& popup_data : g.OpenPopupStack)
    {
        ImGuiWindow* popup_window = popup_data.Window;
        if (popup_window == NULL || !(popup_window->Flags & ImGuiWindowFlags_Modal))
            continue;
        if (!popup_window->Active && !popup_window->WasActive)      // Check WasActive, because this code may run before popup renders on current frame, also check Active to handle newly created windows.
            continue;
        if (window == NULL)                                         // FindBlockingModal(NULL) test for if FocusWindow(NULL) is naturally possible via a mouse click.
            return popup_window;
        if (IsWindowWithinBeginStackOf(window, popup_window))       // Window may be over modal
            continue;
        return popup_window;                                        // Place window right below first block modal
    }
    return NULL;
}

// Push a new Dear ImGui window to add widgets to.
// - A default window called "Debug" is automatically stacked at the beginning of every frame so you can use widgets without explicitly calling a Begin/End pair.
// - Begin/End can be called multiple times during the frame with the same window name to append content.
// - The window name is used as a unique identifier to preserve window information across frames (and save rudimentary information to the .ini file).
//   You can use the "##" or "###" markers to use the same label with different id, or same id with different label. See documentation at the top of this file.
// - Return false when window is collapsed, so you can early out in your code. You always need to call ImGui::End() even if false is returned.
// - Passing 'bool* p_open' displays a Close button on the upper-right corner of the window, the pointed value will be set to false when the button is pressed.
bool ImGui::Begin(const char* name, bool* p_open, ImGuiWindowFlags flags)
{
    ImGuiContext& g = *GImGui;
    const ImGuiStyle& style = g.Style;
    IM_ASSERT(name != NULL && name[0] != '\0');     // Window name required
    IM_ASSERT(g.WithinFrameScope);                  // Forgot to call ImGui::NewFrame()
    IM_ASSERT(g.FrameCountEnded != g.FrameCount);   // Called ImGui::Render() or ImGui::EndFrame() and haven't called ImGui::NewFrame() again yet

    // Find or create
    ImGuiWindow* window = FindWindowByName(name);
    const bool window_just_created = (window == NULL);
    if (window_just_created)
        window = CreateNewWindow(name, flags);

    // Automatically disable manual moving/resizing when NoInputs is set
    if ((flags & ImGuiWindowFlags_NoInputs) == ImGuiWindowFlags_NoInputs)
        flags |= ImGuiWindowFlags_NoMove | ImGuiWindowFlags_NoResize;

    if (flags & ImGuiWindowFlags_NavFlattened)
        IM_ASSERT(flags & ImGuiWindowFlags_ChildWindow);

    const int current_frame = g.FrameCount;
    const bool first_begin_of_the_frame = (window->LastFrameActive != current_frame);
    window->IsFallbackWindow = (g.CurrentWindowStack.Size == 0 && g.WithinFrameScopeWithImplicitWindow);

    // Update the Appearing flag (note: the BeginDocked() path may also set this to true later)
    bool window_just_activated_by_user = (window->LastFrameActive < current_frame - 1); // Not using !WasActive because the implicit "Debug" window would always toggle off->on
    if (flags & ImGuiWindowFlags_Popup)
    {
        ImGuiPopupData& popup_ref = g.OpenPopupStack[g.BeginPopupStack.Size];
        window_just_activated_by_user |= (window->PopupId != popup_ref.PopupId); // We recycle popups so treat window as activated if popup id changed
        window_just_activated_by_user |= (window != popup_ref.Window);
    }

    // Update Flags, LastFrameActive, BeginOrderXXX fields
    const bool window_was_appearing = window->Appearing;
    if (first_begin_of_the_frame)
    {
        UpdateWindowInFocusOrderList(window, window_just_created, flags);
        window->Appearing = window_just_activated_by_user;
        if (window->Appearing)
            SetWindowConditionAllowFlags(window, ImGuiCond_Appearing, true);
        window->FlagsPreviousFrame = window->Flags;
        window->Flags = (ImGuiWindowFlags)flags;
        window->ChildFlags = (g.NextWindowData.Flags & ImGuiNextWindowDataFlags_HasChildFlags) ? g.NextWindowData.ChildFlags : 0;
        window->LastFrameActive = current_frame;
        window->LastTimeActive = (float)g.Time;
        window->BeginOrderWithinParent = 0;
        window->BeginOrderWithinContext = (short)(g.WindowsActiveCount++);
    }
    else
    {
        flags = window->Flags;
    }

    // Docking
    // (NB: during the frame dock nodes are created, it is possible that (window->DockIsActive == false) even though (window->DockNode->Windows.Size > 1)
    IM_ASSERT(window->DockNode == NULL || window->DockNodeAsHost == NULL); // Cannot be both
    if (g.NextWindowData.Flags & ImGuiNextWindowDataFlags_HasDock)
        SetWindowDock(window, g.NextWindowData.DockId, g.NextWindowData.DockCond);
    if (first_begin_of_the_frame)
    {
        bool has_dock_node = (window->DockId != 0 || window->DockNode != NULL);
        bool new_auto_dock_node = !has_dock_node && GetWindowAlwaysWantOwnTabBar(window);
        bool dock_node_was_visible = window->DockNodeIsVisible;
        bool dock_tab_was_visible = window->DockTabIsVisible;
        if (has_dock_node || new_auto_dock_node)
        {
            BeginDocked(window, p_open);
            flags = window->Flags;
            if (window->DockIsActive)
            {
                IM_ASSERT(window->DockNode != NULL);
                g.NextWindowData.Flags &= ~ImGuiNextWindowDataFlags_HasSizeConstraint; // Docking currently override constraints
            }

            // Amend the Appearing flag
            if (window->DockTabIsVisible && !dock_tab_was_visible && dock_node_was_visible && !window->Appearing && !window_was_appearing)
            {
                window->Appearing = true;
                SetWindowConditionAllowFlags(window, ImGuiCond_Appearing, true);
            }
        }
        else
        {
            window->DockIsActive = window->DockNodeIsVisible = window->DockTabIsVisible = false;
        }
    }

    // Parent window is latched only on the first call to Begin() of the frame, so further append-calls can be done from a different window stack
    ImGuiWindow* parent_window_in_stack = (window->DockIsActive && window->DockNode->HostWindow) ? window->DockNode->HostWindow : g.CurrentWindowStack.empty() ? NULL : g.CurrentWindowStack.back().Window;
    ImGuiWindow* parent_window = first_begin_of_the_frame ? ((flags & (ImGuiWindowFlags_ChildWindow | ImGuiWindowFlags_Popup)) ? parent_window_in_stack : NULL) : window->ParentWindow;
    IM_ASSERT(parent_window != NULL || !(flags & ImGuiWindowFlags_ChildWindow));

    // We allow window memory to be compacted so recreate the base stack when needed.
    if (window->IDStack.Size == 0)
        window->IDStack.push_back(window->ID);

    // Add to stack
    g.CurrentWindow = window;
    ImGuiWindowStackData window_stack_data;
    window_stack_data.Window = window;
    window_stack_data.ParentLastItemDataBackup = g.LastItemData;
    window_stack_data.StackSizesOnBegin.SetToContextState(&g);
    g.CurrentWindowStack.push_back(window_stack_data);
    if (flags & ImGuiWindowFlags_ChildMenu)
        g.BeginMenuCount++;

    // Update ->RootWindow and others pointers (before any possible call to FocusWindow)
    if (first_begin_of_the_frame)
    {
        UpdateWindowParentAndRootLinks(window, flags, parent_window);
        window->ParentWindowInBeginStack = parent_window_in_stack;
    }

    // Add to focus scope stack
    // We intentionally set g.CurrentWindow to NULL to prevent usage until when the viewport is set, then will call SetCurrentWindow()
    PushFocusScope(window->ID);
    window->NavRootFocusScopeId = g.CurrentFocusScopeId;
    g.CurrentWindow = NULL;

    // Add to popup stack
    if (flags & ImGuiWindowFlags_Popup)
    {
        ImGuiPopupData& popup_ref = g.OpenPopupStack[g.BeginPopupStack.Size];
        popup_ref.Window = window;
        popup_ref.ParentNavLayer = parent_window_in_stack->DC.NavLayerCurrent;
        g.BeginPopupStack.push_back(popup_ref);
        window->PopupId = popup_ref.PopupId;
    }

    // Process SetNextWindow***() calls
    // (FIXME: Consider splitting the HasXXX flags into X/Y components
    bool window_pos_set_by_api = false;
    bool window_size_x_set_by_api = false, window_size_y_set_by_api = false;
    if (g.NextWindowData.Flags & ImGuiNextWindowDataFlags_HasPos)
    {
        window_pos_set_by_api = (window->SetWindowPosAllowFlags & g.NextWindowData.PosCond) != 0;
        if (window_pos_set_by_api && ImLengthSqr(g.NextWindowData.PosPivotVal) > 0.00001f)
        {
            // May be processed on the next frame if this is our first frame and we are measuring size
            // FIXME: Look into removing the branch so everything can go through this same code path for consistency.
            window->SetWindowPosVal = g.NextWindowData.PosVal;
            window->SetWindowPosPivot = g.NextWindowData.PosPivotVal;
            window->SetWindowPosAllowFlags &= ~(ImGuiCond_Once | ImGuiCond_FirstUseEver | ImGuiCond_Appearing);
        }
        else
        {
            SetWindowPos(window, g.NextWindowData.PosVal, g.NextWindowData.PosCond);
        }
    }
    if (g.NextWindowData.Flags & ImGuiNextWindowDataFlags_HasSize)
    {
        window_size_x_set_by_api = (window->SetWindowSizeAllowFlags & g.NextWindowData.SizeCond) != 0 && (g.NextWindowData.SizeVal.x > 0.0f);
        window_size_y_set_by_api = (window->SetWindowSizeAllowFlags & g.NextWindowData.SizeCond) != 0 && (g.NextWindowData.SizeVal.y > 0.0f);
        if ((window->ChildFlags & ImGuiChildFlags_ResizeX) && (window->SetWindowSizeAllowFlags & ImGuiCond_FirstUseEver) == 0) // Axis-specific conditions for BeginChild()
            g.NextWindowData.SizeVal.x = window->SizeFull.x;
        if ((window->ChildFlags & ImGuiChildFlags_ResizeY) && (window->SetWindowSizeAllowFlags & ImGuiCond_FirstUseEver) == 0)
            g.NextWindowData.SizeVal.y = window->SizeFull.y;
        SetWindowSize(window, g.NextWindowData.SizeVal, g.NextWindowData.SizeCond);
    }
    if (g.NextWindowData.Flags & ImGuiNextWindowDataFlags_HasScroll)
    {
        if (g.NextWindowData.ScrollVal.x >= 0.0f)
        {
            window->ScrollTarget.x = g.NextWindowData.ScrollVal.x;
            window->ScrollTargetCenterRatio.x = 0.0f;
        }
        if (g.NextWindowData.ScrollVal.y >= 0.0f)
        {
            window->ScrollTarget.y = g.NextWindowData.ScrollVal.y;
            window->ScrollTargetCenterRatio.y = 0.0f;
        }
    }
    if (g.NextWindowData.Flags & ImGuiNextWindowDataFlags_HasContentSize)
        window->ContentSizeExplicit = g.NextWindowData.ContentSizeVal;
    else if (first_begin_of_the_frame)
        window->ContentSizeExplicit = ImVec2(0.0f, 0.0f);
    if (g.NextWindowData.Flags & ImGuiNextWindowDataFlags_HasWindowClass)
        window->WindowClass = g.NextWindowData.WindowClass;
    if (g.NextWindowData.Flags & ImGuiNextWindowDataFlags_HasCollapsed)
        SetWindowCollapsed(window, g.NextWindowData.CollapsedVal, g.NextWindowData.CollapsedCond);
    if (g.NextWindowData.Flags & ImGuiNextWindowDataFlags_HasFocus)
        FocusWindow(window);
    if (window->Appearing)
        SetWindowConditionAllowFlags(window, ImGuiCond_Appearing, false);

    // When reusing window again multiple times a frame, just append content (don't need to setup again)
    if (first_begin_of_the_frame)
    {
        // Initialize
        const bool window_is_child_tooltip = (flags & ImGuiWindowFlags_ChildWindow) && (flags & ImGuiWindowFlags_Tooltip); // FIXME-WIP: Undocumented behavior of Child+Tooltip for pinned tooltip (#1345)
        const bool window_just_appearing_after_hidden_for_resize = (window->HiddenFramesCannotSkipItems > 0);
        window->Active = true;
        window->HasCloseButton = (p_open != NULL);
        window->ClipRect = ImVec4(-FLT_MAX, -FLT_MAX, +FLT_MAX, +FLT_MAX);
        window->IDStack.resize(1);
        window->DrawList->_ResetForNewFrame();
        window->DC.CurrentTableIdx = -1;
        if (flags & ImGuiWindowFlags_DockNodeHost)
        {
            window->DrawList->ChannelsSplit(2);
            window->DrawList->ChannelsSetCurrent(DOCKING_HOST_DRAW_CHANNEL_FG); // Render decorations on channel 1 as we will render the backgrounds manually later
        }

        // Restore buffer capacity when woken from a compacted state, to avoid
        if (window->MemoryCompacted)
            GcAwakeTransientWindowBuffers(window);

        // Update stored window name when it changes (which can _only_ happen with the "###" operator, so the ID would stay unchanged).
        // The title bar always display the 'name' parameter, so we only update the string storage if it needs to be visible to the end-user elsewhere.
        bool window_title_visible_elsewhere = false;
        if ((window->Viewport && window->Viewport->Window == window) || (window->DockIsActive))
            window_title_visible_elsewhere = true;
        else if (g.NavWindowingListWindow != NULL && (window->Flags & ImGuiWindowFlags_NoNavFocus) == 0)   // Window titles visible when using CTRL+TAB
            window_title_visible_elsewhere = true;
        if (window_title_visible_elsewhere && !window_just_created && strcmp(name, window->Name) != 0)
        {
            size_t buf_len = (size_t)window->NameBufLen;
            window->Name = ImStrdupcpy(window->Name, &buf_len, name);
            window->NameBufLen = (int)buf_len;
        }

        // UPDATE CONTENTS SIZE, UPDATE HIDDEN STATUS

        // Update contents size from last frame for auto-fitting (or use explicit size)
        CalcWindowContentSizes(window, &window->ContentSize, &window->ContentSizeIdeal);

        // FIXME: These flags are decremented before they are used. This means that in order to have these fields produce their intended behaviors
        // for one frame we must set them to at least 2, which is counter-intuitive. HiddenFramesCannotSkipItems is a more complicated case because
        // it has a single usage before this code block and may be set below before it is finally checked.
        if (window->HiddenFramesCanSkipItems > 0)
            window->HiddenFramesCanSkipItems--;
        if (window->HiddenFramesCannotSkipItems > 0)
            window->HiddenFramesCannotSkipItems--;
        if (window->HiddenFramesForRenderOnly > 0)
            window->HiddenFramesForRenderOnly--;

        // Hide new windows for one frame until they calculate their size
        if (window_just_created && (!window_size_x_set_by_api || !window_size_y_set_by_api))
            window->HiddenFramesCannotSkipItems = 1;

        // Hide popup/tooltip window when re-opening while we measure size (because we recycle the windows)
        // We reset Size/ContentSize for reappearing popups/tooltips early in this function, so further code won't be tempted to use the old size.
        if (window_just_activated_by_user && (flags & (ImGuiWindowFlags_Popup | ImGuiWindowFlags_Tooltip)) != 0)
        {
            window->HiddenFramesCannotSkipItems = 1;
            if (flags & ImGuiWindowFlags_AlwaysAutoResize)
            {
                if (!window_size_x_set_by_api)
                    window->Size.x = window->SizeFull.x = 0.f;
                if (!window_size_y_set_by_api)
                    window->Size.y = window->SizeFull.y = 0.f;
                window->ContentSize = window->ContentSizeIdeal = ImVec2(0.f, 0.f);
            }
        }

        // SELECT VIEWPORT
        // We need to do this before using any style/font sizes, as viewport with a different DPI may affect font sizes.

        WindowSelectViewport(window);
        SetCurrentViewport(window, window->Viewport);
        window->FontDpiScale = (g.IO.ConfigFlags & ImGuiConfigFlags_DpiEnableScaleFonts) ? window->Viewport->DpiScale : 1.0f;
        SetCurrentWindow(window);
        flags = window->Flags;

        // LOCK BORDER SIZE AND PADDING FOR THE FRAME (so that altering them doesn't cause inconsistencies)
        // We read Style data after the call to UpdateSelectWindowViewport() which might be swapping the style.

        if (!window->DockIsActive && (flags & ImGuiWindowFlags_ChildWindow))
            window->WindowBorderSize = style.ChildBorderSize;
        else
            window->WindowBorderSize = ((flags & (ImGuiWindowFlags_Popup | ImGuiWindowFlags_Tooltip)) && !(flags & ImGuiWindowFlags_Modal)) ? style.PopupBorderSize : style.WindowBorderSize;
        window->WindowPadding = style.WindowPadding;
        if (!window->DockIsActive && (flags & ImGuiWindowFlags_ChildWindow) && !(flags & ImGuiWindowFlags_Popup) && !(window->ChildFlags & ImGuiChildFlags_AlwaysUseWindowPadding) && window->WindowBorderSize == 0.0f)
            window->WindowPadding = ImVec2(0.0f, (flags & ImGuiWindowFlags_MenuBar) ? style.WindowPadding.y : 0.0f);

        // Lock menu offset so size calculation can use it as menu-bar windows need a minimum size.
        window->DC.MenuBarOffset.x = ImMax(ImMax(window->WindowPadding.x, style.ItemSpacing.x), g.NextWindowData.MenuBarOffsetMinVal.x);
        window->DC.MenuBarOffset.y = g.NextWindowData.MenuBarOffsetMinVal.y;

        bool use_current_size_for_scrollbar_x = window_just_created;
        bool use_current_size_for_scrollbar_y = window_just_created;

        // Collapse window by double-clicking on title bar
        // At this point we don't have a clipping rectangle setup yet, so we can use the title bar area for hit detection and drawing
        if (!(flags & ImGuiWindowFlags_NoTitleBar) && !(flags & ImGuiWindowFlags_NoCollapse) && !window->DockIsActive)
        {
            // We don't use a regular button+id to test for double-click on title bar (mostly due to legacy reason, could be fixed), so verify that we don't have items over the title bar.
            ImRect title_bar_rect = window->TitleBarRect();
            if (g.HoveredWindow == window && g.HoveredId == 0 && g.HoveredIdPreviousFrame == 0 && IsMouseHoveringRect(title_bar_rect.Min, title_bar_rect.Max) && g.IO.MouseClickedCount[0] == 2)
                window->WantCollapseToggle = true;
            if (window->WantCollapseToggle)
            {
                window->Collapsed = !window->Collapsed;
                if (!window->Collapsed)
                    use_current_size_for_scrollbar_y = true;
                MarkIniSettingsDirty(window);
            }
        }
        else
        {
            window->Collapsed = false;
        }
        window->WantCollapseToggle = false;

        // SIZE

        // Outer Decoration Sizes
        // (we need to clear ScrollbarSize immediatly as CalcWindowAutoFitSize() needs it and can be called from other locations).
        const ImVec2 scrollbar_sizes_from_last_frame = window->ScrollbarSizes;
        window->DecoOuterSizeX1 = 0.0f;
        window->DecoOuterSizeX2 = 0.0f;
        window->DecoOuterSizeY1 = window->TitleBarHeight() + window->MenuBarHeight();
        window->DecoOuterSizeY2 = 0.0f;
        window->ScrollbarSizes = ImVec2(0.0f, 0.0f);

        // Calculate auto-fit size, handle automatic resize
        const ImVec2 size_auto_fit = CalcWindowAutoFitSize(window, window->ContentSizeIdeal);
        if ((flags & ImGuiWindowFlags_AlwaysAutoResize) && !window->Collapsed)
        {
            // Using SetNextWindowSize() overrides ImGuiWindowFlags_AlwaysAutoResize, so it can be used on tooltips/popups, etc.
            if (!window_size_x_set_by_api)
            {
                window->SizeFull.x = size_auto_fit.x;
                use_current_size_for_scrollbar_x = true;
            }
            if (!window_size_y_set_by_api)
            {
                window->SizeFull.y = size_auto_fit.y;
                use_current_size_for_scrollbar_y = true;
            }
        }
        else if (window->AutoFitFramesX > 0 || window->AutoFitFramesY > 0)
        {
            // Auto-fit may only grow window during the first few frames
            // We still process initial auto-fit on collapsed windows to get a window width, but otherwise don't honor ImGuiWindowFlags_AlwaysAutoResize when collapsed.
            if (!window_size_x_set_by_api && window->AutoFitFramesX > 0)
            {
                window->SizeFull.x = window->AutoFitOnlyGrows ? ImMax(window->SizeFull.x, size_auto_fit.x) : size_auto_fit.x;
                use_current_size_for_scrollbar_x = true;
            }
            if (!window_size_y_set_by_api && window->AutoFitFramesY > 0)
            {
                window->SizeFull.y = window->AutoFitOnlyGrows ? ImMax(window->SizeFull.y, size_auto_fit.y) : size_auto_fit.y;
                use_current_size_for_scrollbar_y = true;
            }
            if (!window->Collapsed)
                MarkIniSettingsDirty(window);
        }

        // Apply minimum/maximum window size constraints and final size
        window->SizeFull = CalcWindowSizeAfterConstraint(window, window->SizeFull);
        window->Size = window->Collapsed && !(flags & ImGuiWindowFlags_ChildWindow) ? window->TitleBarRect().GetSize() : window->SizeFull;

        // POSITION

        // Popup latch its initial position, will position itself when it appears next frame
        if (window_just_activated_by_user)
        {
            window->AutoPosLastDirection = ImGuiDir_None;
            if ((flags & ImGuiWindowFlags_Popup) != 0 && !(flags & ImGuiWindowFlags_Modal) && !window_pos_set_by_api) // FIXME: BeginPopup() could use SetNextWindowPos()
                window->Pos = g.BeginPopupStack.back().OpenPopupPos;
        }

        // Position child window
        if (flags & ImGuiWindowFlags_ChildWindow)
        {
            IM_ASSERT(parent_window && parent_window->Active);
            window->BeginOrderWithinParent = (short)parent_window->DC.ChildWindows.Size;
            parent_window->DC.ChildWindows.push_back(window);
            if (!(flags & ImGuiWindowFlags_Popup) && !window_pos_set_by_api && !window_is_child_tooltip)
                window->Pos = parent_window->DC.CursorPos;
        }

        const bool window_pos_with_pivot = (window->SetWindowPosVal.x != FLT_MAX && window->HiddenFramesCannotSkipItems == 0);
        if (window_pos_with_pivot)
            SetWindowPos(window, window->SetWindowPosVal - window->Size * window->SetWindowPosPivot, 0); // Position given a pivot (e.g. for centering)
        else if ((flags & ImGuiWindowFlags_ChildMenu) != 0)
            window->Pos = FindBestWindowPosForPopup(window);
        else if ((flags & ImGuiWindowFlags_Popup) != 0 && !window_pos_set_by_api && window_just_appearing_after_hidden_for_resize)
            window->Pos = FindBestWindowPosForPopup(window);
        else if ((flags & ImGuiWindowFlags_Tooltip) != 0 && !window_pos_set_by_api && !window_is_child_tooltip)
            window->Pos = FindBestWindowPosForPopup(window);

        // Late create viewport if we don't fit within our current host viewport.
        if (window->ViewportAllowPlatformMonitorExtend >= 0 && !window->ViewportOwned && !(window->Viewport->Flags & ImGuiViewportFlags_IsMinimized))
            if (!window->Viewport->GetMainRect().Contains(window->Rect()))
            {
                // This is based on the assumption that the DPI will be known ahead (same as the DPI of the selection done in UpdateSelectWindowViewport)
                //ImGuiViewport* old_viewport = window->Viewport;
                window->Viewport = AddUpdateViewport(window, window->ID, window->Pos, window->Size, ImGuiViewportFlags_NoFocusOnAppearing);

                // FIXME-DPI
                //IM_ASSERT(old_viewport->DpiScale == window->Viewport->DpiScale); // FIXME-DPI: Something went wrong
                SetCurrentViewport(window, window->Viewport);
                window->FontDpiScale = (g.IO.ConfigFlags & ImGuiConfigFlags_DpiEnableScaleFonts) ? window->Viewport->DpiScale : 1.0f;
                SetCurrentWindow(window);
            }

        if (window->ViewportOwned)
            WindowSyncOwnedViewport(window, parent_window_in_stack);

        // Calculate the range of allowed position for that window (to be movable and visible past safe area padding)
        // When clamping to stay visible, we will enforce that window->Pos stays inside of visibility_rect.
        ImRect viewport_rect(window->Viewport->GetMainRect());
        ImRect viewport_work_rect(window->Viewport->GetWorkRect());
        ImVec2 visibility_padding = ImMax(style.DisplayWindowPadding, style.DisplaySafeAreaPadding);
        ImRect visibility_rect(viewport_work_rect.Min + visibility_padding, viewport_work_rect.Max - visibility_padding);

        // Clamp position/size so window stays visible within its viewport or monitor
        // Ignore zero-sized display explicitly to avoid losing positions if a window manager reports zero-sized window when initializing or minimizing.
        // FIXME: Similar to code in GetWindowAllowedExtentRect()
        if (!window_pos_set_by_api && !(flags & ImGuiWindowFlags_ChildWindow))
        {
            if (!window->ViewportOwned && viewport_rect.GetWidth() > 0 && viewport_rect.GetHeight() > 0.0f)
            {
                ClampWindowPos(window, visibility_rect);
            }
            else if (window->ViewportOwned && g.PlatformIO.Monitors.Size > 0)
            {
                // Lost windows (e.g. a monitor disconnected) will naturally moved to the fallback/dummy monitor aka the main viewport.
                const ImGuiPlatformMonitor* monitor = GetViewportPlatformMonitor(window->Viewport);
                visibility_rect.Min = monitor->WorkPos + visibility_padding;
                visibility_rect.Max = monitor->WorkPos + monitor->WorkSize - visibility_padding;
                ClampWindowPos(window, visibility_rect);
            }
        }
        window->Pos = ImTrunc(window->Pos);

        // Lock window rounding for the frame (so that altering them doesn't cause inconsistencies)
        // Large values tend to lead to variety of artifacts and are not recommended.
        if (window->ViewportOwned || window->DockIsActive)
            window->WindowRounding = 0.0f;
        else
            window->WindowRounding = (flags & ImGuiWindowFlags_ChildWindow) ? style.ChildRounding : ((flags & ImGuiWindowFlags_Popup) && !(flags & ImGuiWindowFlags_Modal)) ? style.PopupRounding : style.WindowRounding;

        // For windows with title bar or menu bar, we clamp to FrameHeight(FontSize + FramePadding.y * 2.0f) to completely hide artifacts.
        //if ((window->Flags & ImGuiWindowFlags_MenuBar) || !(window->Flags & ImGuiWindowFlags_NoTitleBar))
        //    window->WindowRounding = ImMin(window->WindowRounding, g.FontSize + style.FramePadding.y * 2.0f);

        // Apply window focus (new and reactivated windows are moved to front)
        bool want_focus = false;
        if (window_just_activated_by_user && !(flags & ImGuiWindowFlags_NoFocusOnAppearing))
        {
            if (flags & ImGuiWindowFlags_Popup)
                want_focus = true;
            else if ((window->DockIsActive || (flags & ImGuiWindowFlags_ChildWindow) == 0) && !(flags & ImGuiWindowFlags_Tooltip))
                want_focus = true;
        }

        // [Test Engine] Register whole window in the item system (before submitting further decorations)
#ifdef IMGUI_ENABLE_TEST_ENGINE
        if (g.TestEngineHookItems)
        {
            IM_ASSERT(window->IDStack.Size == 1);
            window->IDStack.Size = 0; // As window->IDStack[0] == window->ID here, make sure TestEngine doesn't erroneously see window as parent of itself.
            IMGUI_TEST_ENGINE_ITEM_ADD(window->ID, window->Rect(), NULL);
            IMGUI_TEST_ENGINE_ITEM_INFO(window->ID, window->Name, (g.HoveredWindow == window) ? ImGuiItemStatusFlags_HoveredRect : 0);
            window->IDStack.Size = 1;
        }
#endif

        // Decide if we are going to handle borders and resize grips
        const bool handle_borders_and_resize_grips = (window->DockNodeAsHost || !window->DockIsActive);

        // Handle manual resize: Resize Grips, Borders, Gamepad
        int border_hovered = -1, border_held = -1;
        ImU32 resize_grip_col[4] = {};
        const int resize_grip_count = (window->Flags & ImGuiWindowFlags_ChildWindow) ? 0 : g.IO.ConfigWindowsResizeFromEdges ? 2 : 1; // Allow resize from lower-left if we have the mouse cursor feedback for it.
        const float resize_grip_draw_size = IM_TRUNC(ImMax(g.FontSize * 1.10f, window->WindowRounding + 1.0f + g.FontSize * 0.2f));
        if (handle_borders_and_resize_grips && !window->Collapsed)
            if (int auto_fit_mask = UpdateWindowManualResize(window, size_auto_fit, &border_hovered, &border_held, resize_grip_count, &resize_grip_col[0], visibility_rect))
            {
                if (auto_fit_mask & (1 << ImGuiAxis_X))
                    use_current_size_for_scrollbar_x = true;
                if (auto_fit_mask & (1 << ImGuiAxis_Y))
                    use_current_size_for_scrollbar_y = true;
            }
        window->ResizeBorderHovered = (signed char)border_hovered;
        window->ResizeBorderHeld = (signed char)border_held;

        // Synchronize window --> viewport again and one last time (clamping and manual resize may have affected either)
        if (window->ViewportOwned)
        {
            if (!window->Viewport->PlatformRequestMove)
                window->Viewport->Pos = window->Pos;
            if (!window->Viewport->PlatformRequestResize)
                window->Viewport->Size = window->Size;
            window->Viewport->UpdateWorkRect();
            viewport_rect = window->Viewport->GetMainRect();
        }

        // Save last known viewport position within the window itself (so it can be saved in .ini file and restored)
        window->ViewportPos = window->Viewport->Pos;

        // SCROLLBAR VISIBILITY

        // Update scrollbar visibility (based on the Size that was effective during last frame or the auto-resized Size).
        if (!window->Collapsed)
        {
            // When reading the current size we need to read it after size constraints have been applied.
            // Intentionally use previous frame values for InnerRect and ScrollbarSizes.
            // And when we use window->DecorationUp here it doesn't have ScrollbarSizes.y applied yet.
            ImVec2 avail_size_from_current_frame = ImVec2(window->SizeFull.x, window->SizeFull.y - (window->DecoOuterSizeY1 + window->DecoOuterSizeY2));
            ImVec2 avail_size_from_last_frame = window->InnerRect.GetSize() + scrollbar_sizes_from_last_frame;
            ImVec2 needed_size_from_last_frame = window_just_created ? ImVec2(0, 0) : window->ContentSize + window->WindowPadding * 2.0f;
            float size_x_for_scrollbars = use_current_size_for_scrollbar_x ? avail_size_from_current_frame.x : avail_size_from_last_frame.x;
            float size_y_for_scrollbars = use_current_size_for_scrollbar_y ? avail_size_from_current_frame.y : avail_size_from_last_frame.y;
            //bool scrollbar_y_from_last_frame = window->ScrollbarY; // FIXME: May want to use that in the ScrollbarX expression? How many pros vs cons?
            window->ScrollbarY = (flags & ImGuiWindowFlags_AlwaysVerticalScrollbar) || ((needed_size_from_last_frame.y > size_y_for_scrollbars) && !(flags & ImGuiWindowFlags_NoScrollbar));
            window->ScrollbarX = (flags & ImGuiWindowFlags_AlwaysHorizontalScrollbar) || ((needed_size_from_last_frame.x > size_x_for_scrollbars - (window->ScrollbarY ? style.ScrollbarSize : 0.0f)) && !(flags & ImGuiWindowFlags_NoScrollbar) && (flags & ImGuiWindowFlags_HorizontalScrollbar));
            if (window->ScrollbarX && !window->ScrollbarY)
                window->ScrollbarY = (needed_size_from_last_frame.y > size_y_for_scrollbars) && !(flags & ImGuiWindowFlags_NoScrollbar);
            window->ScrollbarSizes = ImVec2(window->ScrollbarY ? style.ScrollbarSize : 0.0f, window->ScrollbarX ? style.ScrollbarSize : 0.0f);

            // Amend the partially filled window->DecorationXXX values.
            window->DecoOuterSizeX2 += window->ScrollbarSizes.x;
            window->DecoOuterSizeY2 += window->ScrollbarSizes.y;
        }

        // UPDATE RECTANGLES (1- THOSE NOT AFFECTED BY SCROLLING)
        // Update various regions. Variables they depend on should be set above in this function.
        // We set this up after processing the resize grip so that our rectangles doesn't lag by a frame.

        // Outer rectangle
        // Not affected by window border size. Used by:
        // - FindHoveredWindow() (w/ extra padding when border resize is enabled)
        // - Begin() initial clipping rect for drawing window background and borders.
        // - Begin() clipping whole child
        const ImRect host_rect = ((flags & ImGuiWindowFlags_ChildWindow) && !(flags & ImGuiWindowFlags_Popup) && !window_is_child_tooltip) ? parent_window->ClipRect : viewport_rect;
        const ImRect outer_rect = window->Rect();
        const ImRect title_bar_rect = window->TitleBarRect();
        window->OuterRectClipped = outer_rect;
        if (window->DockIsActive)
            window->OuterRectClipped.Min.y += window->TitleBarHeight();
        window->OuterRectClipped.ClipWith(host_rect);

        // Inner rectangle
        // Not affected by window border size. Used by:
        // - InnerClipRect
        // - ScrollToRectEx()
        // - NavUpdatePageUpPageDown()
        // - Scrollbar()
        window->InnerRect.Min.x = window->Pos.x + window->DecoOuterSizeX1;
        window->InnerRect.Min.y = window->Pos.y + window->DecoOuterSizeY1;
        window->InnerRect.Max.x = window->Pos.x + window->Size.x - window->DecoOuterSizeX2;
        window->InnerRect.Max.y = window->Pos.y + window->Size.y - window->DecoOuterSizeY2;

        // Inner clipping rectangle.
        // Will extend a little bit outside the normal work region.
        // This is to allow e.g. Selectable or CollapsingHeader or some separators to cover that space.
        // Force round operator last to ensure that e.g. (int)(max.x-min.x) in user's render code produce correct result.
        // Note that if our window is collapsed we will end up with an inverted (~null) clipping rectangle which is the correct behavior.
        // Affected by window/frame border size. Used by:
        // - Begin() initial clip rect
        float top_border_size = (((flags & ImGuiWindowFlags_MenuBar) || !(flags & ImGuiWindowFlags_NoTitleBar)) ? style.FrameBorderSize : window->WindowBorderSize);
        window->InnerClipRect.Min.x = ImFloor(0.5f + window->InnerRect.Min.x + ImMax(ImTrunc(window->WindowPadding.x * 0.5f), window->WindowBorderSize));
        window->InnerClipRect.Min.y = ImFloor(0.5f + window->InnerRect.Min.y + top_border_size);
        window->InnerClipRect.Max.x = ImFloor(0.5f + window->InnerRect.Max.x - ImMax(ImTrunc(window->WindowPadding.x * 0.5f), window->WindowBorderSize));
        window->InnerClipRect.Max.y = ImFloor(0.5f + window->InnerRect.Max.y - window->WindowBorderSize);
        window->InnerClipRect.ClipWithFull(host_rect);

        // Default item width. Make it proportional to window size if window manually resizes
        if (window->Size.x > 0.0f && !(flags & ImGuiWindowFlags_Tooltip) && !(flags & ImGuiWindowFlags_AlwaysAutoResize))
            window->ItemWidthDefault = ImTrunc(window->Size.x * 0.65f);
        else
            window->ItemWidthDefault = ImTrunc(g.FontSize * 16.0f);

        // SCROLLING

        // Lock down maximum scrolling
        // The value of ScrollMax are ahead from ScrollbarX/ScrollbarY which is intentionally using InnerRect from previous rect in order to accommodate
        // for right/bottom aligned items without creating a scrollbar.
        window->ScrollMax.x = ImMax(0.0f, window->ContentSize.x + window->WindowPadding.x * 2.0f - window->InnerRect.GetWidth());
        window->ScrollMax.y = ImMax(0.0f, window->ContentSize.y + window->WindowPadding.y * 2.0f - window->InnerRect.GetHeight());

        // Apply scrolling
        window->Scroll = CalcNextScrollFromScrollTargetAndClamp(window);
        window->ScrollTarget = ImVec2(FLT_MAX, FLT_MAX);
        window->DecoInnerSizeX1 = window->DecoInnerSizeY1 = 0.0f;

        // DRAWING

        // Setup draw list and outer clipping rectangle
        IM_ASSERT(window->DrawList->CmdBuffer.Size == 1 && window->DrawList->CmdBuffer[0].ElemCount == 0);
        window->DrawList->PushTextureID(g.Font->ContainerAtlas->TexID);
        PushClipRect(host_rect.Min, host_rect.Max, false);

        // Child windows can render their decoration (bg color, border, scrollbars, etc.) within their parent to save a draw call (since 1.71)
        // When using overlapping child windows, this will break the assumption that child z-order is mapped to submission order.
        // FIXME: User code may rely on explicit sorting of overlapping child window and would need to disable this somehow. Please get in contact if you are affected (github #4493)
        const bool is_undocked_or_docked_visible = !window->DockIsActive || window->DockTabIsVisible;
        if (is_undocked_or_docked_visible)
        {
            bool render_decorations_in_parent = false;
            if ((flags & ImGuiWindowFlags_ChildWindow) && !(flags & ImGuiWindowFlags_Popup) && !window_is_child_tooltip)
            {
                // - We test overlap with the previous child window only (testing all would end up being O(log N) not a good investment here)
                // - We disable this when the parent window has zero vertices, which is a common pattern leading to laying out multiple overlapping childs
                ImGuiWindow* previous_child = parent_window->DC.ChildWindows.Size >= 2 ? parent_window->DC.ChildWindows[parent_window->DC.ChildWindows.Size - 2] : NULL;
                bool previous_child_overlapping = previous_child ? previous_child->Rect().Overlaps(window->Rect()) : false;
                bool parent_is_empty = (parent_window->DrawList->VtxBuffer.Size == 0);
                if (window->DrawList->CmdBuffer.back().ElemCount == 0 && !parent_is_empty && !previous_child_overlapping)
                    render_decorations_in_parent = true;
            }
            if (render_decorations_in_parent)
                window->DrawList = parent_window->DrawList;

            // Handle title bar, scrollbar, resize grips and resize borders
            const ImGuiWindow* window_to_highlight = g.NavWindowingTarget ? g.NavWindowingTarget : g.NavWindow;
            const bool title_bar_is_highlight = want_focus || (window_to_highlight && (window->RootWindowForTitleBarHighlight == window_to_highlight->RootWindowForTitleBarHighlight || (window->DockNode && window->DockNode == window_to_highlight->DockNode)));
            RenderWindowDecorations(window, title_bar_rect, title_bar_is_highlight, handle_borders_and_resize_grips, resize_grip_count, resize_grip_col, resize_grip_draw_size);

            if (render_decorations_in_parent)
                window->DrawList = &window->DrawListInst;
        }

        // UPDATE RECTANGLES (2- THOSE AFFECTED BY SCROLLING)

        // Work rectangle.
        // Affected by window padding and border size. Used by:
        // - Columns() for right-most edge
        // - TreeNode(), CollapsingHeader() for right-most edge
        // - BeginTabBar() for right-most edge
        const bool allow_scrollbar_x = !(flags & ImGuiWindowFlags_NoScrollbar) && (flags & ImGuiWindowFlags_HorizontalScrollbar);
        const bool allow_scrollbar_y = !(flags & ImGuiWindowFlags_NoScrollbar);
        const float work_rect_size_x = (window->ContentSizeExplicit.x != 0.0f ? window->ContentSizeExplicit.x : ImMax(allow_scrollbar_x ? window->ContentSize.x : 0.0f, window->Size.x - window->WindowPadding.x * 2.0f - (window->DecoOuterSizeX1 + window->DecoOuterSizeX2)));
        const float work_rect_size_y = (window->ContentSizeExplicit.y != 0.0f ? window->ContentSizeExplicit.y : ImMax(allow_scrollbar_y ? window->ContentSize.y : 0.0f, window->Size.y - window->WindowPadding.y * 2.0f - (window->DecoOuterSizeY1 + window->DecoOuterSizeY2)));
        window->WorkRect.Min.x = ImTrunc(window->InnerRect.Min.x - window->Scroll.x + ImMax(window->WindowPadding.x, window->WindowBorderSize));
        window->WorkRect.Min.y = ImTrunc(window->InnerRect.Min.y - window->Scroll.y + ImMax(window->WindowPadding.y, window->WindowBorderSize));
        window->WorkRect.Max.x = window->WorkRect.Min.x + work_rect_size_x;
        window->WorkRect.Max.y = window->WorkRect.Min.y + work_rect_size_y;
        window->ParentWorkRect = window->WorkRect;

        // [LEGACY] Content Region
        // FIXME-OBSOLETE: window->ContentRegionRect.Max is currently very misleading / partly faulty, but some BeginChild() patterns relies on it.
        // Unless explicit content size is specified by user, this currently represent the region leading to no scrolling.
        // Used by:
        // - Mouse wheel scrolling + many other things
        window->ContentRegionRect.Min.x = window->Pos.x - window->Scroll.x + window->WindowPadding.x + window->DecoOuterSizeX1;
        window->ContentRegionRect.Min.y = window->Pos.y - window->Scroll.y + window->WindowPadding.y + window->DecoOuterSizeY1;
        window->ContentRegionRect.Max.x = window->ContentRegionRect.Min.x + (window->ContentSizeExplicit.x != 0.0f ? window->ContentSizeExplicit.x : (window->Size.x - window->WindowPadding.x * 2.0f - (window->DecoOuterSizeX1 + window->DecoOuterSizeX2)));
        window->ContentRegionRect.Max.y = window->ContentRegionRect.Min.y + (window->ContentSizeExplicit.y != 0.0f ? window->ContentSizeExplicit.y : (window->Size.y - window->WindowPadding.y * 2.0f - (window->DecoOuterSizeY1 + window->DecoOuterSizeY2)));

        // Setup drawing context
        // (NB: That term "drawing context / DC" lost its meaning a long time ago. Initially was meant to hold transient data only. Nowadays difference between window-> and window->DC-> is dubious.)
        window->DC.Indent.x = window->DecoOuterSizeX1 + window->WindowPadding.x - window->Scroll.x;
        window->DC.GroupOffset.x = 0.0f;
        window->DC.ColumnsOffset.x = 0.0f;

        // Record the loss of precision of CursorStartPos which can happen due to really large scrolling amount.
        // This is used by clipper to compensate and fix the most common use case of large scroll area. Easy and cheap, next best thing compared to switching everything to double or ImU64.
        double start_pos_highp_x = (double)window->Pos.x + window->WindowPadding.x - (double)window->Scroll.x + window->DecoOuterSizeX1 + window->DC.ColumnsOffset.x;
        double start_pos_highp_y = (double)window->Pos.y + window->WindowPadding.y - (double)window->Scroll.y + window->DecoOuterSizeY1;
        window->DC.CursorStartPos  = ImVec2((float)start_pos_highp_x, (float)start_pos_highp_y);
        window->DC.CursorStartPosLossyness = ImVec2((float)(start_pos_highp_x - window->DC.CursorStartPos.x), (float)(start_pos_highp_y - window->DC.CursorStartPos.y));
        window->DC.CursorPos = window->DC.CursorStartPos;
        window->DC.CursorPosPrevLine = window->DC.CursorPos;
        window->DC.CursorMaxPos = window->DC.CursorStartPos;
        window->DC.IdealMaxPos = window->DC.CursorStartPos;
        window->DC.CurrLineSize = window->DC.PrevLineSize = ImVec2(0.0f, 0.0f);
        window->DC.CurrLineTextBaseOffset = window->DC.PrevLineTextBaseOffset = 0.0f;
        window->DC.IsSameLine = window->DC.IsSetPos = false;

        window->DC.NavLayerCurrent = ImGuiNavLayer_Main;
        window->DC.NavLayersActiveMask = window->DC.NavLayersActiveMaskNext;
        window->DC.NavLayersActiveMaskNext = 0x00;
        window->DC.NavIsScrollPushableX = true;
        window->DC.NavHideHighlightOneFrame = false;
        window->DC.NavWindowHasScrollY = (window->ScrollMax.y > 0.0f);

        window->DC.MenuBarAppending = false;
        window->DC.MenuColumns.Update(style.ItemSpacing.x, window_just_activated_by_user);
        window->DC.TreeDepth = 0;
        window->DC.TreeJumpToParentOnPopMask = 0x00;
        window->DC.ChildWindows.resize(0);
        window->DC.StateStorage = &window->StateStorage;
        window->DC.CurrentColumns = NULL;
        window->DC.LayoutType = ImGuiLayoutType_Vertical;
        window->DC.ParentLayoutType = parent_window ? parent_window->DC.LayoutType : ImGuiLayoutType_Vertical;

        window->DC.ItemWidth = window->ItemWidthDefault;
        window->DC.TextWrapPos = -1.0f; // disabled
        window->DC.ItemWidthStack.resize(0);
        window->DC.TextWrapPosStack.resize(0);

        if (window->AutoFitFramesX > 0)
            window->AutoFitFramesX--;
        if (window->AutoFitFramesY > 0)
            window->AutoFitFramesY--;

        // Apply focus (we need to call FocusWindow() AFTER setting DC.CursorStartPos so our initial navigation reference rectangle can start around there)
        // We ImGuiFocusRequestFlags_UnlessBelowModal to:
        // - Avoid focusing a window that is created outside of a modal. This will prevent active modal from being closed.
        // - Position window behind the modal that is not a begin-parent of this window.
        if (want_focus)
            FocusWindow(window, ImGuiFocusRequestFlags_UnlessBelowModal);
        if (want_focus && window == g.NavWindow)
            NavInitWindow(window, false); // <-- this is in the way for us to be able to defer and sort reappearing FocusWindow() calls

        // Close requested by platform window (apply to all windows in this viewport)
        if (p_open != NULL && window->Viewport->PlatformRequestClose && window->Viewport != GetMainViewport())
        {
            IMGUI_DEBUG_LOG_VIEWPORT("[viewport] Window '%s' closed by PlatformRequestClose\n", window->Name);
            *p_open = false;
            g.NavWindowingToggleLayer = false; // Assume user mapped PlatformRequestClose on ALT-F4 so we disable ALT for menu toggle. False positive not an issue. // FIXME-NAV: Try removing.
        }

        // Title bar
        if (!(flags & ImGuiWindowFlags_NoTitleBar) && !window->DockIsActive)
            RenderWindowTitleBarContents(window, ImRect(title_bar_rect.Min.x + window->WindowBorderSize, title_bar_rect.Min.y, title_bar_rect.Max.x - window->WindowBorderSize, title_bar_rect.Max.y), name, p_open);

        // Clear hit test shape every frame
        window->HitTestHoleSize.x = window->HitTestHoleSize.y = 0;

        // Pressing CTRL+C while holding on a window copy its content to the clipboard
        // This works but 1. doesn't handle multiple Begin/End pairs, 2. recursing into another Begin/End pair - so we need to work that out and add better logging scope.
        // Maybe we can support CTRL+C on every element?
        /*
        //if (g.NavWindow == window && g.ActiveId == 0)
        if (g.ActiveId == window->MoveId)
            if (g.IO.KeyCtrl && IsKeyPressed(ImGuiKey_C))
                LogToClipboard();
        */

        if (g.IO.ConfigFlags & ImGuiConfigFlags_DockingEnable)
        {
            // Docking: Dragging a dockable window (or any of its child) turns it into a drag and drop source.
            // We need to do this _before_ we overwrite window->DC.LastItemId below because BeginDockableDragDropSource() also overwrites it.
            if (g.MovingWindow == window && (window->RootWindowDockTree->Flags & ImGuiWindowFlags_NoDocking) == 0)
                BeginDockableDragDropSource(window);

            // Docking: Any dockable window can act as a target. For dock node hosts we call BeginDockableDragDropTarget() in DockNodeUpdate() instead.
            if (g.DragDropActive && !(flags & ImGuiWindowFlags_NoDocking))
                if (g.MovingWindow == NULL || g.MovingWindow->RootWindowDockTree != window)
                    if ((window == window->RootWindowDockTree) && !(window->Flags & ImGuiWindowFlags_DockNodeHost))
                        BeginDockableDragDropTarget(window);
        }

        // We fill last item data based on Title Bar/Tab, in order for IsItemHovered() and IsItemActive() to be usable after Begin().
        // This is useful to allow creating context menus on title bar only, etc.
        if (window->DockIsActive)
            SetLastItemData(window->MoveId, g.CurrentItemFlags, window->DockTabItemStatusFlags, window->DockTabItemRect);
        else
            SetLastItemData(window->MoveId, g.CurrentItemFlags, IsMouseHoveringRect(title_bar_rect.Min, title_bar_rect.Max, false) ? ImGuiItemStatusFlags_HoveredRect : 0, title_bar_rect);

        // [DEBUG]
#ifndef IMGUI_DISABLE_DEBUG_TOOLS
        if (g.DebugLocateId != 0 && (window->ID == g.DebugLocateId || window->MoveId == g.DebugLocateId))
            DebugLocateItemResolveWithLastItem();
#endif

        // [Test Engine] Register title bar / tab with MoveId.
#ifdef IMGUI_ENABLE_TEST_ENGINE
        if (!(window->Flags & ImGuiWindowFlags_NoTitleBar))
            IMGUI_TEST_ENGINE_ITEM_ADD(g.LastItemData.ID, g.LastItemData.Rect, &g.LastItemData);
#endif
    }
    else
    {
        // Append
        SetCurrentViewport(window, window->Viewport);
        SetCurrentWindow(window);
    }

    if (!(flags & ImGuiWindowFlags_DockNodeHost))
        PushClipRect(window->InnerClipRect.Min, window->InnerClipRect.Max, true);

    // Clear 'accessed' flag last thing (After PushClipRect which will set the flag. We want the flag to stay false when the default "Debug" window is unused)
    window->WriteAccessed = false;
    window->BeginCount++;
    g.NextWindowData.ClearFlags();

    // Update visibility
    if (first_begin_of_the_frame)
    {
        // When we are about to select this tab (which will only be visible on the _next frame_), flag it with a non-zero HiddenFramesCannotSkipItems.
        // This will have the important effect of actually returning true in Begin() and not setting SkipItems, allowing an earlier submission of the window contents.
        // This is analogous to regular windows being hidden from one frame.
        // It is especially important as e.g. nested TabBars would otherwise generate flicker in the form of one empty frame, or focus requests won't be processed.
        if (window->DockIsActive && !window->DockTabIsVisible)
        {
            if (window->LastFrameJustFocused == g.FrameCount)
                window->HiddenFramesCannotSkipItems = 1;
            else
                window->HiddenFramesCanSkipItems = 1;
        }

        if ((flags & ImGuiWindowFlags_ChildWindow) && !(flags & ImGuiWindowFlags_ChildMenu))
        {
            // Child window can be out of sight and have "negative" clip windows.
            // Mark them as collapsed so commands are skipped earlier (we can't manually collapse them because they have no title bar).
            IM_ASSERT((flags& ImGuiWindowFlags_NoTitleBar) != 0 || window->DockIsActive);
            const bool nav_request = (flags & ImGuiWindowFlags_NavFlattened) && (g.NavAnyRequest && g.NavWindow && g.NavWindow->RootWindowForNav == window->RootWindowForNav);
            if (!g.LogEnabled && !nav_request)
                if (window->OuterRectClipped.Min.x >= window->OuterRectClipped.Max.x || window->OuterRectClipped.Min.y >= window->OuterRectClipped.Max.y)
                {
                    if (window->AutoFitFramesX > 0 || window->AutoFitFramesY > 0)
                        window->HiddenFramesCannotSkipItems = 1;
                    else
                        window->HiddenFramesCanSkipItems = 1;
                }

            // Hide along with parent or if parent is collapsed
            if (parent_window && (parent_window->Collapsed || parent_window->HiddenFramesCanSkipItems > 0))
                window->HiddenFramesCanSkipItems = 1;
            if (parent_window && (parent_window->Collapsed || parent_window->HiddenFramesCannotSkipItems > 0))
                window->HiddenFramesCannotSkipItems = 1;
        }

        // Don't render if style alpha is 0.0 at the time of Begin(). This is arbitrary and inconsistent but has been there for a long while (may remove at some point)
        if (style.Alpha <= 0.0f)
            window->HiddenFramesCanSkipItems = 1;

        // Update the Hidden flag
        bool hidden_regular = (window->HiddenFramesCanSkipItems > 0) || (window->HiddenFramesCannotSkipItems > 0);
        window->Hidden = hidden_regular || (window->HiddenFramesForRenderOnly > 0);

        // Disable inputs for requested number of frames
        if (window->DisableInputsFrames > 0)
        {
            window->DisableInputsFrames--;
            window->Flags |= ImGuiWindowFlags_NoInputs;
        }

        // Update the SkipItems flag, used to early out of all items functions (no layout required)
        bool skip_items = false;
        if (window->Collapsed || !window->Active || hidden_regular)
            if (window->AutoFitFramesX <= 0 && window->AutoFitFramesY <= 0 && window->HiddenFramesCannotSkipItems <= 0)
                skip_items = true;
        window->SkipItems = skip_items;

        // Restore NavLayersActiveMaskNext to previous value when not visible, so a CTRL+Tab back can use a safe value.
        if (window->SkipItems)
            window->DC.NavLayersActiveMaskNext = window->DC.NavLayersActiveMask;

        // Sanity check: there are two spots which can set Appearing = true
        // - when 'window_just_activated_by_user' is set -> HiddenFramesCannotSkipItems is set -> SkipItems always false
        // - in BeginDocked() path when DockNodeIsVisible == DockTabIsVisible == true -> hidden _should_ be all zero // FIXME: Not formally proven, hence the assert.
        if (window->SkipItems && !window->Appearing)
            IM_ASSERT(window->Appearing == false); // Please report on GitHub if this triggers: https://github.com/ocornut/imgui/issues/4177
    }

    // [DEBUG] io.ConfigDebugBeginReturnValue override return value to test Begin/End and BeginChild/EndChild behaviors.
    // (The implicit fallback window is NOT automatically ended allowing it to always be able to receive commands without crashing)
    if (!window->IsFallbackWindow && ((g.IO.ConfigDebugBeginReturnValueOnce && window_just_created) || (g.IO.ConfigDebugBeginReturnValueLoop && g.DebugBeginReturnValueCullDepth == g.CurrentWindowStack.Size)))
    {
        if (window->AutoFitFramesX > 0) { window->AutoFitFramesX++; }
        if (window->AutoFitFramesY > 0) { window->AutoFitFramesY++; }
        return false;
    }

    return !window->SkipItems;
}

void ImGui::End()
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;

    // Error checking: verify that user hasn't called End() too many times!
    if (g.CurrentWindowStack.Size <= 1 && g.WithinFrameScopeWithImplicitWindow)
    {
        IM_ASSERT_USER_ERROR(g.CurrentWindowStack.Size > 1, "Calling End() too many times!");
        return;
    }
    IM_ASSERT(g.CurrentWindowStack.Size > 0);

    // Error checking: verify that user doesn't directly call End() on a child window.
    if ((window->Flags & ImGuiWindowFlags_ChildWindow) && !(window->Flags & ImGuiWindowFlags_DockNodeHost) && !window->DockIsActive)
        IM_ASSERT_USER_ERROR(g.WithinEndChild, "Must call EndChild() and not End()!");

    // Close anything that is open
    if (window->DC.CurrentColumns)
        EndColumns();
    if (!(window->Flags & ImGuiWindowFlags_DockNodeHost))   // Pop inner window clip rectangle
        PopClipRect();
    PopFocusScope();

    // Stop logging
    if (!(window->Flags & ImGuiWindowFlags_ChildWindow))    // FIXME: add more options for scope of logging
        LogFinish();

    if (window->DC.IsSetPos)
        ErrorCheckUsingSetCursorPosToExtendParentBoundaries();

    // Docking: report contents sizes to parent to allow for auto-resize
    if (window->DockNode && window->DockTabIsVisible)
        if (ImGuiWindow* host_window = window->DockNode->HostWindow)         // FIXME-DOCK
            host_window->DC.CursorMaxPos = window->DC.CursorMaxPos + window->WindowPadding - host_window->WindowPadding;

    // Pop from window stack
    g.LastItemData = g.CurrentWindowStack.back().ParentLastItemDataBackup;
    if (window->Flags & ImGuiWindowFlags_ChildMenu)
        g.BeginMenuCount--;
    if (window->Flags & ImGuiWindowFlags_Popup)
        g.BeginPopupStack.pop_back();
    g.CurrentWindowStack.back().StackSizesOnBegin.CompareWithContextState(&g);
    g.CurrentWindowStack.pop_back();
    SetCurrentWindow(g.CurrentWindowStack.Size == 0 ? NULL : g.CurrentWindowStack.back().Window);
    if (g.CurrentWindow)
        SetCurrentViewport(g.CurrentWindow, g.CurrentWindow->Viewport);
}

void ImGui::BringWindowToFocusFront(ImGuiWindow* window)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(window == window->RootWindow);

    const int cur_order = window->FocusOrder;
    IM_ASSERT(g.WindowsFocusOrder[cur_order] == window);
    if (g.WindowsFocusOrder.back() == window)
        return;

    const int new_order = g.WindowsFocusOrder.Size - 1;
    for (int n = cur_order; n < new_order; n++)
    {
        g.WindowsFocusOrder[n] = g.WindowsFocusOrder[n + 1];
        g.WindowsFocusOrder[n]->FocusOrder--;
        IM_ASSERT(g.WindowsFocusOrder[n]->FocusOrder == n);
    }
    g.WindowsFocusOrder[new_order] = window;
    window->FocusOrder = (short)new_order;
}

void ImGui::BringWindowToDisplayFront(ImGuiWindow* window)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* current_front_window = g.Windows.back();
    if (current_front_window == window || current_front_window->RootWindowDockTree == window) // Cheap early out (could be better)
        return;
    for (int i = g.Windows.Size - 2; i >= 0; i--) // We can ignore the top-most window
        if (g.Windows[i] == window)
        {
            memmove(&g.Windows[i], &g.Windows[i + 1], (size_t)(g.Windows.Size - i - 1) * sizeof(ImGuiWindow*));
            g.Windows[g.Windows.Size - 1] = window;
            break;
        }
}

void ImGui::BringWindowToDisplayBack(ImGuiWindow* window)
{
    ImGuiContext& g = *GImGui;
    if (g.Windows[0] == window)
        return;
    for (int i = 0; i < g.Windows.Size; i++)
        if (g.Windows[i] == window)
        {
            memmove(&g.Windows[1], &g.Windows[0], (size_t)i * sizeof(ImGuiWindow*));
            g.Windows[0] = window;
            break;
        }
}

void ImGui::BringWindowToDisplayBehind(ImGuiWindow* window, ImGuiWindow* behind_window)
{
    IM_ASSERT(window != NULL && behind_window != NULL);
    ImGuiContext& g = *GImGui;
    window = window->RootWindow;
    behind_window = behind_window->RootWindow;
    int pos_wnd = FindWindowDisplayIndex(window);
    int pos_beh = FindWindowDisplayIndex(behind_window);
    if (pos_wnd < pos_beh)
    {
        size_t copy_bytes = (pos_beh - pos_wnd - 1) * sizeof(ImGuiWindow*);
        memmove(&g.Windows.Data[pos_wnd], &g.Windows.Data[pos_wnd + 1], copy_bytes);
        g.Windows[pos_beh - 1] = window;
    }
    else
    {
        size_t copy_bytes = (pos_wnd - pos_beh) * sizeof(ImGuiWindow*);
        memmove(&g.Windows.Data[pos_beh + 1], &g.Windows.Data[pos_beh], copy_bytes);
        g.Windows[pos_beh] = window;
    }
}

int ImGui::FindWindowDisplayIndex(ImGuiWindow* window)
{
    ImGuiContext& g = *GImGui;
    return g.Windows.index_from_ptr(g.Windows.find(window));
}

// Moving window to front of display and set focus (which happens to be back of our sorted list)
void ImGui::FocusWindow(ImGuiWindow* window, ImGuiFocusRequestFlags flags)
{
    ImGuiContext& g = *GImGui;

    // Modal check?
    if ((flags & ImGuiFocusRequestFlags_UnlessBelowModal) && (g.NavWindow != window)) // Early out in common case.
        if (ImGuiWindow* blocking_modal = FindBlockingModal(window))
        {
            IMGUI_DEBUG_LOG_FOCUS("[focus] FocusWindow(\"%s\", UnlessBelowModal): prevented by \"%s\".\n", window ? window->Name : "<NULL>", blocking_modal->Name);
            if (window && window == window->RootWindow && (window->Flags & ImGuiWindowFlags_NoBringToFrontOnFocus) == 0)
                BringWindowToDisplayBehind(window, blocking_modal); // Still bring to right below modal.
            return;
        }

    // Find last focused child (if any) and focus it instead.
    if ((flags & ImGuiFocusRequestFlags_RestoreFocusedChild) && window != NULL)
        window = NavRestoreLastChildNavWindow(window);

    // Apply focus
    if (g.NavWindow != window)
    {
        SetNavWindow(window);
        if (window && g.NavDisableMouseHover)
            g.NavMousePosDirty = true;
        g.NavId = window ? window->NavLastIds[0] : 0; // Restore NavId
        g.NavLayer = ImGuiNavLayer_Main;
        g.NavFocusScopeId = window ? window->NavRootFocusScopeId : 0;
        g.NavIdIsAlive = false;
        g.NavLastValidSelectionUserData = ImGuiSelectionUserData_Invalid;

        // Close popups if any
        ClosePopupsOverWindow(window, false);
    }

    // Move the root window to the top of the pile
    IM_ASSERT(window == NULL || window->RootWindowDockTree != NULL);
    ImGuiWindow* focus_front_window = window ? window->RootWindow : NULL;
    ImGuiWindow* display_front_window = window ? window->RootWindowDockTree : NULL;
    ImGuiDockNode* dock_node = window ? window->DockNode : NULL;
    bool active_id_window_is_dock_node_host = (g.ActiveIdWindow && dock_node && dock_node->HostWindow == g.ActiveIdWindow);

    // Steal active widgets. Some of the cases it triggers includes:
    // - Focus a window while an InputText in another window is active, if focus happens before the old InputText can run.
    // - When using Nav to activate menu items (due to timing of activating on press->new window appears->losing ActiveId)
    // - Using dock host items (tab, collapse button) can trigger this before we redirect the ActiveIdWindow toward the child window.
    if (g.ActiveId != 0 && g.ActiveIdWindow && g.ActiveIdWindow->RootWindow != focus_front_window)
        if (!g.ActiveIdNoClearOnFocusLoss && !active_id_window_is_dock_node_host)
            ClearActiveID();

    // Passing NULL allow to disable keyboard focus
    if (!window)
        return;
    window->LastFrameJustFocused = g.FrameCount;

    // Select in dock node
    // For #2304 we avoid applying focus immediately before the tabbar is visible.
    //if (dock_node && dock_node->TabBar)
    //    dock_node->TabBar->SelectedTabId = dock_node->TabBar->NextSelectedTabId = window->TabId;

    // Bring to front
    BringWindowToFocusFront(focus_front_window);
    if (((window->Flags | focus_front_window->Flags | display_front_window->Flags) & ImGuiWindowFlags_NoBringToFrontOnFocus) == 0)
        BringWindowToDisplayFront(display_front_window);
}

void ImGui::FocusTopMostWindowUnderOne(ImGuiWindow* under_this_window, ImGuiWindow* ignore_window, ImGuiViewport* filter_viewport, ImGuiFocusRequestFlags flags)
{
    ImGuiContext& g = *GImGui;
    int start_idx = g.WindowsFocusOrder.Size - 1;
    if (under_this_window != NULL)
    {
        // Aim at root window behind us, if we are in a child window that's our own root (see #4640)
        int offset = -1;
        while (under_this_window->Flags & ImGuiWindowFlags_ChildWindow)
        {
            under_this_window = under_this_window->ParentWindow;
            offset = 0;
        }
        start_idx = FindWindowFocusIndex(under_this_window) + offset;
    }
    for (int i = start_idx; i >= 0; i--)
    {
        // We may later decide to test for different NoXXXInputs based on the active navigation input (mouse vs nav) but that may feel more confusing to the user.
        ImGuiWindow* window = g.WindowsFocusOrder[i];
        if (window == ignore_window || !window->WasActive)
            continue;
        if (filter_viewport != NULL && window->Viewport != filter_viewport)
            continue;
        if ((window->Flags & (ImGuiWindowFlags_NoMouseInputs | ImGuiWindowFlags_NoNavInputs)) != (ImGuiWindowFlags_NoMouseInputs | ImGuiWindowFlags_NoNavInputs))
        {
            // FIXME-DOCK: When ImGuiFocusRequestFlags_RestoreFocusedChild is set...
            // This is failing (lagging by one frame) for docked windows.
            // If A and B are docked into window and B disappear, at the NewFrame() call site window->NavLastChildNavWindow will still point to B.
            // We might leverage the tab order implicitly stored in window->DockNodeAsHost->TabBar (essentially the 'most_recently_selected_tab' code in tab bar will do that but on next update)
            // to tell which is the "previous" window. Or we may leverage 'LastFrameFocused/LastFrameJustFocused' and have this function handle child window itself?
            FocusWindow(window, flags);
            return;
        }
    }
    FocusWindow(NULL, flags);
}

// Important: this alone doesn't alter current ImDrawList state. This is called by PushFont/PopFont only.
void ImGui::SetCurrentFont(ImFont* font)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(font && font->IsLoaded());    // Font Atlas not created. Did you call io.Fonts->GetTexDataAsRGBA32 / GetTexDataAsAlpha8 ?
    IM_ASSERT(font->Scale > 0.0f);
    g.Font = font;
    g.FontBaseSize = ImMax(1.0f, g.IO.FontGlobalScale * g.Font->FontSize * g.Font->Scale);
    g.FontSize = g.CurrentWindow ? g.CurrentWindow->CalcFontSize() : 0.0f;

    ImFontAtlas* atlas = g.Font->ContainerAtlas;
    g.DrawListSharedData.TexUvWhitePixel = atlas->TexUvWhitePixel;
    g.DrawListSharedData.TexUvLines = atlas->TexUvLines;
    g.DrawListSharedData.Font = g.Font;
    g.DrawListSharedData.FontSize = g.FontSize;
}

void ImGui::PushFont(ImFont* font)
{
    ImGuiContext& g = *GImGui;
    if (!font)
        font = GetDefaultFont();
    SetCurrentFont(font);
    g.FontStack.push_back(font);
    g.CurrentWindow->DrawList->PushTextureID(font->ContainerAtlas->TexID);
}

void  ImGui::PopFont()
{
    ImGuiContext& g = *GImGui;
    g.CurrentWindow->DrawList->PopTextureID();
    g.FontStack.pop_back();
    SetCurrentFont(g.FontStack.empty() ? GetDefaultFont() : g.FontStack.back());
}

void ImGui::PushItemFlag(ImGuiItemFlags option, bool enabled)
{
    ImGuiContext& g = *GImGui;
    ImGuiItemFlags item_flags = g.CurrentItemFlags;
    IM_ASSERT(item_flags == g.ItemFlagsStack.back());
    if (enabled)
        item_flags |= option;
    else
        item_flags &= ~option;
    g.CurrentItemFlags = item_flags;
    g.ItemFlagsStack.push_back(item_flags);
}

void ImGui::PopItemFlag()
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(g.ItemFlagsStack.Size > 1); // Too many calls to PopItemFlag() - we always leave a 0 at the bottom of the stack.
    g.ItemFlagsStack.pop_back();
    g.CurrentItemFlags = g.ItemFlagsStack.back();
}

// BeginDisabled()/EndDisabled()
// - Those can be nested but it cannot be used to enable an already disabled section (a single BeginDisabled(true) in the stack is enough to keep everything disabled)
// - Visually this is currently altering alpha, but it is expected that in a future styling system this would work differently.
// - Feedback welcome at https://github.com/ocornut/imgui/issues/211
// - BeginDisabled(false) essentially does nothing useful but is provided to facilitate use of boolean expressions. If you can avoid calling BeginDisabled(False)/EndDisabled() best to avoid it.
// - Optimized shortcuts instead of PushStyleVar() + PushItemFlag()
void ImGui::BeginDisabled(bool disabled)
{
    ImGuiContext& g = *GImGui;
    bool was_disabled = (g.CurrentItemFlags & ImGuiItemFlags_Disabled) != 0;
    if (!was_disabled && disabled)
    {
        g.DisabledAlphaBackup = g.Style.Alpha;
        g.Style.Alpha *= g.Style.DisabledAlpha; // PushStyleVar(ImGuiStyleVar_Alpha, g.Style.Alpha * g.Style.DisabledAlpha);
    }
    if (was_disabled || disabled)
        g.CurrentItemFlags |= ImGuiItemFlags_Disabled;
    g.ItemFlagsStack.push_back(g.CurrentItemFlags);
    g.DisabledStackSize++;
}

void ImGui::EndDisabled()
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(g.DisabledStackSize > 0);
    g.DisabledStackSize--;
    bool was_disabled = (g.CurrentItemFlags & ImGuiItemFlags_Disabled) != 0;
    //PopItemFlag();
    g.ItemFlagsStack.pop_back();
    g.CurrentItemFlags = g.ItemFlagsStack.back();
    if (was_disabled && (g.CurrentItemFlags & ImGuiItemFlags_Disabled) == 0)
        g.Style.Alpha = g.DisabledAlphaBackup; //PopStyleVar();
}

void ImGui::PushTabStop(bool tab_stop)
{
    PushItemFlag(ImGuiItemFlags_NoTabStop, !tab_stop);
}

void ImGui::PopTabStop()
{
    PopItemFlag();
}

void ImGui::PushButtonRepeat(bool repeat)
{
    PushItemFlag(ImGuiItemFlags_ButtonRepeat, repeat);
}

void ImGui::PopButtonRepeat()
{
    PopItemFlag();
}

void ImGui::PushTextWrapPos(float wrap_pos_x)
{
    ImGuiWindow* window = GetCurrentWindow();
    window->DC.TextWrapPosStack.push_back(window->DC.TextWrapPos);
    window->DC.TextWrapPos = wrap_pos_x;
}

void ImGui::PopTextWrapPos()
{
    ImGuiWindow* window = GetCurrentWindow();
    window->DC.TextWrapPos = window->DC.TextWrapPosStack.back();
    window->DC.TextWrapPosStack.pop_back();
}

static ImGuiWindow* GetCombinedRootWindow(ImGuiWindow* window, bool popup_hierarchy, bool dock_hierarchy)
{
    ImGuiWindow* last_window = NULL;
    while (last_window != window)
    {
        last_window = window;
        window = window->RootWindow;
        if (popup_hierarchy)
            window = window->RootWindowPopupTree;
    if (dock_hierarchy)
      window = window->RootWindowDockTree;
  }
    return window;
}

bool ImGui::IsWindowChildOf(ImGuiWindow* window, ImGuiWindow* potential_parent, bool popup_hierarchy, bool dock_hierarchy)
{
    ImGuiWindow* window_root = GetCombinedRootWindow(window, popup_hierarchy, dock_hierarchy);
    if (window_root == potential_parent)
        return true;
    while (window != NULL)
    {
        if (window == potential_parent)
            return true;
        if (window == window_root) // end of chain
            return false;
        window = window->ParentWindow;
    }
    return false;
}

bool ImGui::IsWindowWithinBeginStackOf(ImGuiWindow* window, ImGuiWindow* potential_parent)
{
    if (window->RootWindow == potential_parent)
        return true;
    while (window != NULL)
    {
        if (window == potential_parent)
            return true;
        window = window->ParentWindowInBeginStack;
    }
    return false;
}

bool ImGui::IsWindowAbove(ImGuiWindow* potential_above, ImGuiWindow* potential_below)
{
    ImGuiContext& g = *GImGui;

    // It would be saner to ensure that display layer is always reflected in the g.Windows[] order, which would likely requires altering all manipulations of that array
    const int display_layer_delta = GetWindowDisplayLayer(potential_above) - GetWindowDisplayLayer(potential_below);
    if (display_layer_delta != 0)
        return display_layer_delta > 0;

    for (int i = g.Windows.Size - 1; i >= 0; i--)
    {
        ImGuiWindow* candidate_window = g.Windows[i];
        if (candidate_window == potential_above)
            return true;
        if (candidate_window == potential_below)
            return false;
    }
    return false;
}

bool ImGui::IsWindowHovered(ImGuiHoveredFlags flags)
{
    IM_ASSERT((flags & ~ImGuiHoveredFlags_AllowedMaskForIsWindowHovered) == 0 && "Invalid flags for IsWindowHovered()!");

    ImGuiContext& g = *GImGui;
    ImGuiWindow* ref_window = g.HoveredWindow;
    ImGuiWindow* cur_window = g.CurrentWindow;
    if (ref_window == NULL)
        return false;

    if ((flags & ImGuiHoveredFlags_AnyWindow) == 0)
    {
        IM_ASSERT(cur_window); // Not inside a Begin()/End()
        const bool popup_hierarchy = (flags & ImGuiHoveredFlags_NoPopupHierarchy) == 0;
        const bool dock_hierarchy = (flags & ImGuiHoveredFlags_DockHierarchy) != 0;
        if (flags & ImGuiHoveredFlags_RootWindow)
            cur_window = GetCombinedRootWindow(cur_window, popup_hierarchy, dock_hierarchy);

        bool result;
        if (flags & ImGuiHoveredFlags_ChildWindows)
            result = IsWindowChildOf(ref_window, cur_window, popup_hierarchy, dock_hierarchy);
        else
            result = (ref_window == cur_window);
        if (!result)
            return false;
    }

    if (!IsWindowContentHoverable(ref_window, flags))
        return false;
    if (!(flags & ImGuiHoveredFlags_AllowWhenBlockedByActiveItem))
        if (g.ActiveId != 0 && !g.ActiveIdAllowOverlap && g.ActiveId != ref_window->MoveId)
            return false;

    // When changing hovered window we requires a bit of stationary delay before activating hover timer.
    // FIXME: We don't support delay other than stationary one for now, other delay would need a way
    // to fullfill the possibility that multiple IsWindowHovered() with varying flag could return true
    // for different windows of the hierarchy. Possibly need a Hash(Current+Flags) ==> (Timer) cache.
    // We can implement this for _Stationary because the data is linked to HoveredWindow rather than CurrentWindow.
    if (flags & ImGuiHoveredFlags_ForTooltip)
        flags = ApplyHoverFlagsForTooltip(flags, g.Style.HoverFlagsForTooltipMouse);
    if ((flags & ImGuiHoveredFlags_Stationary) != 0 && g.HoverWindowUnlockedStationaryId != ref_window->ID)
        return false;

    return true;
}

bool ImGui::IsWindowFocused(ImGuiFocusedFlags flags)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* ref_window = g.NavWindow;
    ImGuiWindow* cur_window = g.CurrentWindow;

    if (ref_window == NULL)
        return false;
    if (flags & ImGuiFocusedFlags_AnyWindow)
        return true;

    IM_ASSERT(cur_window); // Not inside a Begin()/End()
    const bool popup_hierarchy = (flags & ImGuiFocusedFlags_NoPopupHierarchy) == 0;
    const bool dock_hierarchy = (flags & ImGuiFocusedFlags_DockHierarchy) != 0;
    if (flags & ImGuiHoveredFlags_RootWindow)
        cur_window = GetCombinedRootWindow(cur_window, popup_hierarchy, dock_hierarchy);

    if (flags & ImGuiHoveredFlags_ChildWindows)
        return IsWindowChildOf(ref_window, cur_window, popup_hierarchy, dock_hierarchy);
    else
        return (ref_window == cur_window);
}

ImGuiID ImGui::GetWindowDockID()
{
    ImGuiContext& g = *GImGui;
    return g.CurrentWindow->DockId;
}

bool ImGui::IsWindowDocked()
{
    ImGuiContext& g = *GImGui;
    return g.CurrentWindow->DockIsActive;
}

// Can we focus this window with CTRL+TAB (or PadMenu + PadFocusPrev/PadFocusNext)
// Note that NoNavFocus makes the window not reachable with CTRL+TAB but it can still be focused with mouse or programmatically.
// If you want a window to never be focused, you may use the e.g. NoInputs flag.
bool ImGui::IsWindowNavFocusable(ImGuiWindow* window)
{
    return window->WasActive && window == window->RootWindow && !(window->Flags & ImGuiWindowFlags_NoNavFocus);
}

float ImGui::GetWindowWidth()
{
    ImGuiWindow* window = GImGui->CurrentWindow;
    return window->Size.x;
}

float ImGui::GetWindowHeight()
{
    ImGuiWindow* window = GImGui->CurrentWindow;
    return window->Size.y;
}

ImVec2 ImGui::GetWindowPos()
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    return window->Pos;
}

void ImGui::SetWindowPos(ImGuiWindow* window, const ImVec2& pos, ImGuiCond cond)
{
    // Test condition (NB: bit 0 is always true) and clear flags for next time
    if (cond && (window->SetWindowPosAllowFlags & cond) == 0)
        return;

    IM_ASSERT(cond == 0 || ImIsPowerOfTwo(cond)); // Make sure the user doesn't attempt to combine multiple condition flags.
    window->SetWindowPosAllowFlags &= ~(ImGuiCond_Once | ImGuiCond_FirstUseEver | ImGuiCond_Appearing);
    window->SetWindowPosVal = ImVec2(FLT_MAX, FLT_MAX);

    // Set
    const ImVec2 old_pos = window->Pos;
    window->Pos = ImTrunc(pos);
    ImVec2 offset = window->Pos - old_pos;
    if (offset.x == 0.0f && offset.y == 0.0f)
        return;
    MarkIniSettingsDirty(window);
    // FIXME: share code with TranslateWindow(), need to confirm whether the 3 rect modified by TranslateWindow() are desirable here.
    window->DC.CursorPos += offset;         // As we happen to move the window while it is being appended to (which is a bad idea - will smear) let's at least offset the cursor
    window->DC.CursorMaxPos += offset;      // And more importantly we need to offset CursorMaxPos/CursorStartPos this so ContentSize calculation doesn't get affected.
    window->DC.IdealMaxPos += offset;
    window->DC.CursorStartPos += offset;
}

void ImGui::SetWindowPos(const ImVec2& pos, ImGuiCond cond)
{
    ImGuiWindow* window = GetCurrentWindowRead();
    SetWindowPos(window, pos, cond);
}

void ImGui::SetWindowPos(const char* name, const ImVec2& pos, ImGuiCond cond)
{
    if (ImGuiWindow* window = FindWindowByName(name))
        SetWindowPos(window, pos, cond);
}

ImVec2 ImGui::GetWindowSize()
{
    ImGuiWindow* window = GetCurrentWindowRead();
    return window->Size;
}

void ImGui::SetWindowSize(ImGuiWindow* window, const ImVec2& size, ImGuiCond cond)
{
    // Test condition (NB: bit 0 is always true) and clear flags for next time
    if (cond && (window->SetWindowSizeAllowFlags & cond) == 0)
        return;

    IM_ASSERT(cond == 0 || ImIsPowerOfTwo(cond)); // Make sure the user doesn't attempt to combine multiple condition flags.
    window->SetWindowSizeAllowFlags &= ~(ImGuiCond_Once | ImGuiCond_FirstUseEver | ImGuiCond_Appearing);

    // Enable auto-fit (not done in BeginChild() path unless appearing or combined with ImGuiChildFlags_AlwaysAutoResize)
    if ((window->Flags & ImGuiWindowFlags_ChildWindow) == 0 || window->Appearing || (window->ChildFlags & ImGuiChildFlags_AlwaysAutoResize) != 0)
        window->AutoFitFramesX = (size.x <= 0.0f) ? 2 : 0;
    if ((window->Flags & ImGuiWindowFlags_ChildWindow) == 0 || window->Appearing || (window->ChildFlags & ImGuiChildFlags_AlwaysAutoResize) != 0)
        window->AutoFitFramesY = (size.y <= 0.0f) ? 2 : 0;

    // Set
    ImVec2 old_size = window->SizeFull;
    if (size.x <= 0.0f)
        window->AutoFitOnlyGrows = false;
    else
        window->SizeFull.x = IM_TRUNC(size.x);
    if (size.y <= 0.0f)
        window->AutoFitOnlyGrows = false;
    else
        window->SizeFull.y = IM_TRUNC(size.y);
    if (old_size.x != window->SizeFull.x || old_size.y != window->SizeFull.y)
        MarkIniSettingsDirty(window);
}

void ImGui::SetWindowSize(const ImVec2& size, ImGuiCond cond)
{
    SetWindowSize(GImGui->CurrentWindow, size, cond);
}

void ImGui::SetWindowSize(const char* name, const ImVec2& size, ImGuiCond cond)
{
    if (ImGuiWindow* window = FindWindowByName(name))
        SetWindowSize(window, size, cond);
}

void ImGui::SetWindowCollapsed(ImGuiWindow* window, bool collapsed, ImGuiCond cond)
{
    // Test condition (NB: bit 0 is always true) and clear flags for next time
    if (cond && (window->SetWindowCollapsedAllowFlags & cond) == 0)
        return;
    window->SetWindowCollapsedAllowFlags &= ~(ImGuiCond_Once | ImGuiCond_FirstUseEver | ImGuiCond_Appearing);

    // Set
    window->Collapsed = collapsed;
}

void ImGui::SetWindowHitTestHole(ImGuiWindow* window, const ImVec2& pos, const ImVec2& size)
{
    IM_ASSERT(window->HitTestHoleSize.x == 0);     // We don't support multiple holes/hit test filters
    window->HitTestHoleSize = ImVec2ih(size);
    window->HitTestHoleOffset = ImVec2ih(pos - window->Pos);
}

void ImGui::SetWindowHiddendAndSkipItemsForCurrentFrame(ImGuiWindow* window)
{
    window->Hidden = window->SkipItems = true;
    window->HiddenFramesCanSkipItems = 1;
}

void ImGui::SetWindowCollapsed(bool collapsed, ImGuiCond cond)
{
    SetWindowCollapsed(GImGui->CurrentWindow, collapsed, cond);
}

bool ImGui::IsWindowCollapsed()
{
    ImGuiWindow* window = GetCurrentWindowRead();
    return window->Collapsed;
}

bool ImGui::IsWindowAppearing()
{
    ImGuiWindow* window = GetCurrentWindowRead();
    return window->Appearing;
}

void ImGui::SetWindowCollapsed(const char* name, bool collapsed, ImGuiCond cond)
{
    if (ImGuiWindow* window = FindWindowByName(name))
        SetWindowCollapsed(window, collapsed, cond);
}

void ImGui::SetWindowFocus()
{
    FocusWindow(GImGui->CurrentWindow);
}

void ImGui::SetWindowFocus(const char* name)
{
    if (name)
    {
        if (ImGuiWindow* window = FindWindowByName(name))
            FocusWindow(window);
    }
    else
    {
        FocusWindow(NULL);
    }
}

void ImGui::SetNextWindowPos(const ImVec2& pos, ImGuiCond cond, const ImVec2& pivot)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(cond == 0 || ImIsPowerOfTwo(cond)); // Make sure the user doesn't attempt to combine multiple condition flags.
    g.NextWindowData.Flags |= ImGuiNextWindowDataFlags_HasPos;
    g.NextWindowData.PosVal = pos;
    g.NextWindowData.PosPivotVal = pivot;
    g.NextWindowData.PosCond = cond ? cond : ImGuiCond_Always;
    g.NextWindowData.PosUndock = true;
}

void ImGui::SetNextWindowSize(const ImVec2& size, ImGuiCond cond)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(cond == 0 || ImIsPowerOfTwo(cond)); // Make sure the user doesn't attempt to combine multiple condition flags.
    g.NextWindowData.Flags |= ImGuiNextWindowDataFlags_HasSize;
    g.NextWindowData.SizeVal = size;
    g.NextWindowData.SizeCond = cond ? cond : ImGuiCond_Always;
}

void ImGui::SetNextWindowSizeConstraints(const ImVec2& size_min, const ImVec2& size_max, ImGuiSizeCallback custom_callback, void* custom_callback_user_data)
{
    ImGuiContext& g = *GImGui;
    g.NextWindowData.Flags |= ImGuiNextWindowDataFlags_HasSizeConstraint;
    g.NextWindowData.SizeConstraintRect = ImRect(size_min, size_max);
    g.NextWindowData.SizeCallback = custom_callback;
    g.NextWindowData.SizeCallbackUserData = custom_callback_user_data;
}

// Content size = inner scrollable rectangle, padded with WindowPadding.
// SetNextWindowContentSize(ImVec2(100,100) + ImGuiWindowFlags_AlwaysAutoResize will always allow submitting a 100x100 item.
void ImGui::SetNextWindowContentSize(const ImVec2& size)
{
    ImGuiContext& g = *GImGui;
    g.NextWindowData.Flags |= ImGuiNextWindowDataFlags_HasContentSize;
    g.NextWindowData.ContentSizeVal = ImTrunc(size);
}

void ImGui::SetNextWindowScroll(const ImVec2& scroll)
{
    ImGuiContext& g = *GImGui;
    g.NextWindowData.Flags |= ImGuiNextWindowDataFlags_HasScroll;
    g.NextWindowData.ScrollVal = scroll;
}

void ImGui::SetNextWindowCollapsed(bool collapsed, ImGuiCond cond)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(cond == 0 || ImIsPowerOfTwo(cond)); // Make sure the user doesn't attempt to combine multiple condition flags.
    g.NextWindowData.Flags |= ImGuiNextWindowDataFlags_HasCollapsed;
    g.NextWindowData.CollapsedVal = collapsed;
    g.NextWindowData.CollapsedCond = cond ? cond : ImGuiCond_Always;
}

void ImGui::SetNextWindowFocus()
{
    ImGuiContext& g = *GImGui;
    g.NextWindowData.Flags |= ImGuiNextWindowDataFlags_HasFocus;
}

void ImGui::SetNextWindowBgAlpha(float alpha)
{
    ImGuiContext& g = *GImGui;
    g.NextWindowData.Flags |= ImGuiNextWindowDataFlags_HasBgAlpha;
    g.NextWindowData.BgAlphaVal = alpha;
}

void ImGui::SetNextWindowViewport(ImGuiID id)
{
    ImGuiContext& g = *GImGui;
    g.NextWindowData.Flags |= ImGuiNextWindowDataFlags_HasViewport;
    g.NextWindowData.ViewportId = id;
}

void ImGui::SetNextWindowDockID(ImGuiID id, ImGuiCond cond)
{
    ImGuiContext& g = *GImGui;
    g.NextWindowData.Flags |= ImGuiNextWindowDataFlags_HasDock;
    g.NextWindowData.DockCond = cond ? cond : ImGuiCond_Always;
    g.NextWindowData.DockId = id;
}

void ImGui::SetNextWindowClass(const ImGuiWindowClass* window_class)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT((window_class->ViewportFlagsOverrideSet & window_class->ViewportFlagsOverrideClear) == 0); // Cannot set both set and clear for the same bit
    g.NextWindowData.Flags |= ImGuiNextWindowDataFlags_HasWindowClass;
    g.NextWindowData.WindowClass = *window_class;
}

ImDrawList* ImGui::GetWindowDrawList()
{
    ImGuiWindow* window = GetCurrentWindow();
    return window->DrawList;
}

float ImGui::GetWindowDpiScale()
{
    ImGuiContext& g = *GImGui;
    return g.CurrentDpiScale;
}

ImGuiViewport* ImGui::GetWindowViewport()
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(g.CurrentViewport != NULL && g.CurrentViewport == g.CurrentWindow->Viewport);
    return g.CurrentViewport;
}

ImFont* ImGui::GetFont()
{
    return GImGui->Font;
}

float ImGui::GetFontSize()
{
    return GImGui->FontSize;
}

ImVec2 ImGui::GetFontTexUvWhitePixel()
{
    return GImGui->DrawListSharedData.TexUvWhitePixel;
}

void ImGui::SetWindowFontScale(float scale)
{
    IM_ASSERT(scale > 0.0f);
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = GetCurrentWindow();
    window->FontWindowScale = scale;
    g.FontSize = g.DrawListSharedData.FontSize = window->CalcFontSize();
}

void ImGui::PushFocusScope(ImGuiID id)
{
    ImGuiContext& g = *GImGui;
    g.FocusScopeStack.push_back(id);
    g.CurrentFocusScopeId = id;
}

void ImGui::PopFocusScope()
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(g.FocusScopeStack.Size > 0); // Too many PopFocusScope() ?
    g.FocusScopeStack.pop_back();
    g.CurrentFocusScopeId = g.FocusScopeStack.Size ? g.FocusScopeStack.back() : 0;
}

// Focus = move navigation cursor, set scrolling, set focus window.
void ImGui::FocusItem()
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    IMGUI_DEBUG_LOG_FOCUS("FocusItem(0x%08x) in window \"%s\"\n", g.LastItemData.ID, window->Name);
    if (g.DragDropActive || g.MovingWindow != NULL) // FIXME: Opt-in flags for this?
    {
        IMGUI_DEBUG_LOG_FOCUS("FocusItem() ignored while DragDropActive!\n");
        return;
    }

    ImGuiNavMoveFlags move_flags = ImGuiNavMoveFlags_IsTabbing | ImGuiNavMoveFlags_FocusApi | ImGuiNavMoveFlags_NoSetNavHighlight | ImGuiNavMoveFlags_NoSelect;
    ImGuiScrollFlags scroll_flags = window->Appearing ? ImGuiScrollFlags_KeepVisibleEdgeX | ImGuiScrollFlags_AlwaysCenterY : ImGuiScrollFlags_KeepVisibleEdgeX | ImGuiScrollFlags_KeepVisibleEdgeY;
    SetNavWindow(window);
    NavMoveRequestSubmit(ImGuiDir_None, ImGuiDir_Up, move_flags, scroll_flags);
    NavMoveRequestResolveWithLastItem(&g.NavMoveResultLocal);
}

void ImGui::ActivateItemByID(ImGuiID id)
{
    ImGuiContext& g = *GImGui;
    g.NavNextActivateId = id;
    g.NavNextActivateFlags = ImGuiActivateFlags_None;
}

// Note: this will likely be called ActivateItem() once we rework our Focus/Activation system!
// But ActivateItem() should function without altering scroll/focus?
void ImGui::SetKeyboardFocusHere(int offset)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    IM_ASSERT(offset >= -1);    // -1 is allowed but not below
    IMGUI_DEBUG_LOG_FOCUS("SetKeyboardFocusHere(%d) in window \"%s\"\n", offset, window->Name);

    // It makes sense in the vast majority of cases to never interrupt a drag and drop.
    // When we refactor this function into ActivateItem() we may want to make this an option.
    // MovingWindow is protected from most user inputs using SetActiveIdUsingNavAndKeys(), but
    // is also automatically dropped in the event g.ActiveId is stolen.
    if (g.DragDropActive || g.MovingWindow != NULL)
    {
        IMGUI_DEBUG_LOG_FOCUS("SetKeyboardFocusHere() ignored while DragDropActive!\n");
        return;
    }

    SetNavWindow(window);

    ImGuiNavMoveFlags move_flags = ImGuiNavMoveFlags_IsTabbing | ImGuiNavMoveFlags_Activate | ImGuiNavMoveFlags_FocusApi | ImGuiNavMoveFlags_NoSetNavHighlight;
    ImGuiScrollFlags scroll_flags = window->Appearing ? ImGuiScrollFlags_KeepVisibleEdgeX | ImGuiScrollFlags_AlwaysCenterY : ImGuiScrollFlags_KeepVisibleEdgeX | ImGuiScrollFlags_KeepVisibleEdgeY;
    NavMoveRequestSubmit(ImGuiDir_None, offset < 0 ? ImGuiDir_Up : ImGuiDir_Down, move_flags, scroll_flags); // FIXME-NAV: Once we refactor tabbing, add LegacyApi flag to not activate non-inputable.
    if (offset == -1)
    {
        NavMoveRequestResolveWithLastItem(&g.NavMoveResultLocal);
    }
    else
    {
        g.NavTabbingDir = 1;
        g.NavTabbingCounter = offset + 1;
    }
}

void ImGui::SetItemDefaultFocus()
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    if (!window->Appearing)
        return;
    if (g.NavWindow != window->RootWindowForNav || (!g.NavInitRequest && g.NavInitResult.ID == 0) || g.NavLayer != window->DC.NavLayerCurrent)
        return;

    g.NavInitRequest = false;
    NavApplyItemToResult(&g.NavInitResult);
    NavUpdateAnyRequestFlag();

    // Scroll could be done in NavInitRequestApplyResult() via an opt-in flag (we however don't want regular init requests to scroll)
    if (!window->ClipRect.Contains(g.LastItemData.Rect))
        ScrollToRectEx(window, g.LastItemData.Rect, ImGuiScrollFlags_None);
}

void ImGui::SetStateStorage(ImGuiStorage* tree)
{
    ImGuiWindow* window = GImGui->CurrentWindow;
    window->DC.StateStorage = tree ? tree : &window->StateStorage;
}

ImGuiStorage* ImGui::GetStateStorage()
{
    ImGuiWindow* window = GImGui->CurrentWindow;
    return window->DC.StateStorage;
}

void ImGui::PushID(const char* str_id)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    ImGuiID id = window->GetID(str_id);
    window->IDStack.push_back(id);
}

void ImGui::PushID(const char* str_id_begin, const char* str_id_end)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    ImGuiID id = window->GetID(str_id_begin, str_id_end);
    window->IDStack.push_back(id);
}

void ImGui::PushID(const void* ptr_id)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    ImGuiID id = window->GetID(ptr_id);
    window->IDStack.push_back(id);
}

void ImGui::PushID(int int_id)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    ImGuiID id = window->GetID(int_id);
    window->IDStack.push_back(id);
}

// Push a given id value ignoring the ID stack as a seed.
void ImGui::PushOverrideID(ImGuiID id)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    if (g.DebugHookIdInfo == id)
        DebugHookIdInfo(id, ImGuiDataType_ID, NULL, NULL);
    window->IDStack.push_back(id);
}

// Helper to avoid a common series of PushOverrideID -> GetID() -> PopID() call
// (note that when using this pattern, ID Stack Tool will tend to not display the intermediate stack level.
//  for that to work we would need to do PushOverrideID() -> ItemAdd() -> PopID() which would alter widget code a little more)
ImGuiID ImGui::GetIDWithSeed(const char* str, const char* str_end, ImGuiID seed)
{
    ImGuiID id = ImHashStr(str, str_end ? (str_end - str) : 0, seed);
    ImGuiContext& g = *GImGui;
    if (g.DebugHookIdInfo == id)
        DebugHookIdInfo(id, ImGuiDataType_String, str, str_end);
    return id;
}

ImGuiID ImGui::GetIDWithSeed(int n, ImGuiID seed)
{
    ImGuiID id = ImHashData(&n, sizeof(n), seed);
    ImGuiContext& g = *GImGui;
    if (g.DebugHookIdInfo == id)
        DebugHookIdInfo(id, ImGuiDataType_S32, (void*)(intptr_t)n, NULL);
    return id;
}

void ImGui::PopID()
{
    ImGuiWindow* window = GImGui->CurrentWindow;
    IM_ASSERT(window->IDStack.Size > 1); // Too many PopID(), or could be popping in a wrong/different window?
    window->IDStack.pop_back();
}

ImGuiID ImGui::GetID(const char* str_id)
{
    ImGuiWindow* window = GImGui->CurrentWindow;
    return window->GetID(str_id);
}

ImGuiID ImGui::GetID(const char* str_id_begin, const char* str_id_end)
{
    ImGuiWindow* window = GImGui->CurrentWindow;
    return window->GetID(str_id_begin, str_id_end);
}

ImGuiID ImGui::GetID(const void* ptr_id)
{
    ImGuiWindow* window = GImGui->CurrentWindow;
    return window->GetID(ptr_id);
}

bool ImGui::IsRectVisible(const ImVec2& size)
{
    ImGuiWindow* window = GImGui->CurrentWindow;
    return window->ClipRect.Overlaps(ImRect(window->DC.CursorPos, window->DC.CursorPos + size));
}

bool ImGui::IsRectVisible(const ImVec2& rect_min, const ImVec2& rect_max)
{
    ImGuiWindow* window = GImGui->CurrentWindow;
    return window->ClipRect.Overlaps(ImRect(rect_min, rect_max));
}


//-----------------------------------------------------------------------------
// [SECTION] INPUTS
//-----------------------------------------------------------------------------
// - GetKeyData() [Internal]
// - GetKeyIndex() [Internal]
// - GetKeyName()
// - GetKeyChordName() [Internal]
// - CalcTypematicRepeatAmount() [Internal]
// - GetTypematicRepeatRate() [Internal]
// - GetKeyPressedAmount() [Internal]
// - GetKeyMagnitude2d() [Internal]
//-----------------------------------------------------------------------------
// - UpdateKeyRoutingTable() [Internal]
// - GetRoutingIdFromOwnerId() [Internal]
// - GetShortcutRoutingData() [Internal]
// - CalcRoutingScore() [Internal]
// - SetShortcutRouting() [Internal]
// - TestShortcutRouting() [Internal]
//-----------------------------------------------------------------------------
// - IsKeyDown()
// - IsKeyPressed()
// - IsKeyReleased()
//-----------------------------------------------------------------------------
// - IsMouseDown()
// - IsMouseClicked()
// - IsMouseReleased()
// - IsMouseDoubleClicked()
// - GetMouseClickedCount()
// - IsMouseHoveringRect() [Internal]
// - IsMouseDragPastThreshold() [Internal]
// - IsMouseDragging()
// - GetMousePos()
// - SetMousePos() [Internal]
// - GetMousePosOnOpeningCurrentPopup()
// - IsMousePosValid()
// - IsAnyMouseDown()
// - GetMouseDragDelta()
// - ResetMouseDragDelta()
// - GetMouseCursor()
// - SetMouseCursor()
//-----------------------------------------------------------------------------
// - UpdateAliasKey()
// - GetMergedModsFromKeys()
// - UpdateKeyboardInputs()
// - UpdateMouseInputs()
//-----------------------------------------------------------------------------
// - LockWheelingWindow [Internal]
// - FindBestWheelingWindow [Internal]
// - UpdateMouseWheel() [Internal]
//-----------------------------------------------------------------------------
// - SetNextFrameWantCaptureKeyboard()
// - SetNextFrameWantCaptureMouse()
//-----------------------------------------------------------------------------
// - GetInputSourceName() [Internal]
// - DebugPrintInputEvent() [Internal]
// - UpdateInputEvents() [Internal]
//-----------------------------------------------------------------------------
// - GetKeyOwner() [Internal]
// - TestKeyOwner() [Internal]
// - SetKeyOwner() [Internal]
// - SetItemKeyOwner() [Internal]
// - Shortcut() [Internal]
//-----------------------------------------------------------------------------

ImGuiKeyData* ImGui::GetKeyData(ImGuiContext* ctx, ImGuiKey key)
{
    ImGuiContext& g = *ctx;

    // Special storage location for mods
    if (key & ImGuiMod_Mask_)
        key = ConvertSingleModFlagToKey(ctx, key);

#ifndef IMGUI_DISABLE_OBSOLETE_KEYIO
    IM_ASSERT(key >= ImGuiKey_LegacyNativeKey_BEGIN && key < ImGuiKey_NamedKey_END);
    if (IsLegacyKey(key) && g.IO.KeyMap[key] != -1)
        key = (ImGuiKey)g.IO.KeyMap[key];  // Remap native->imgui or imgui->native
#else
    IM_ASSERT(IsNamedKey(key) && "Support for user key indices was dropped in favor of ImGuiKey. Please update backend & user code.");
#endif
    return &g.IO.KeysData[key - ImGuiKey_KeysData_OFFSET];
}

#ifndef IMGUI_DISABLE_OBSOLETE_KEYIO
ImGuiKey ImGui::GetKeyIndex(ImGuiKey key)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(IsNamedKey(key));
    const ImGuiKeyData* key_data = GetKeyData(key);
    return (ImGuiKey)(key_data - g.IO.KeysData);
}
#endif

// Those names a provided for debugging purpose and are not meant to be saved persistently not compared.
static const char* const GKeyNames[] =
{
    "Tab", "LeftArrow", "RightArrow", "UpArrow", "DownArrow", "PageUp", "PageDown",
    "Home", "End", "Insert", "Delete", "Backspace", "Space", "Enter", "Escape",
    "LeftCtrl", "LeftShift", "LeftAlt", "LeftSuper", "RightCtrl", "RightShift", "RightAlt", "RightSuper", "Menu",
    "0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "A", "B", "C", "D", "E", "F", "G", "H",
    "I", "J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z",
    "F1", "F2", "F3", "F4", "F5", "F6", "F7", "F8", "F9", "F10", "F11", "F12",
    "F13", "F14", "F15", "F16", "F17", "F18", "F19", "F20", "F21", "F22", "F23", "F24",
    "Apostrophe", "Comma", "Minus", "Period", "Slash", "Semicolon", "Equal", "LeftBracket",
    "Backslash", "RightBracket", "GraveAccent", "CapsLock", "ScrollLock", "NumLock", "PrintScreen",
    "Pause", "Keypad0", "Keypad1", "Keypad2", "Keypad3", "Keypad4", "Keypad5", "Keypad6",
    "Keypad7", "Keypad8", "Keypad9", "KeypadDecimal", "KeypadDivide", "KeypadMultiply",
    "KeypadSubtract", "KeypadAdd", "KeypadEnter", "KeypadEqual",
    "AppBack", "AppForward",
    "GamepadStart", "GamepadBack",
    "GamepadFaceLeft", "GamepadFaceRight", "GamepadFaceUp", "GamepadFaceDown",
    "GamepadDpadLeft", "GamepadDpadRight", "GamepadDpadUp", "GamepadDpadDown",
    "GamepadL1", "GamepadR1", "GamepadL2", "GamepadR2", "GamepadL3", "GamepadR3",
    "GamepadLStickLeft", "GamepadLStickRight", "GamepadLStickUp", "GamepadLStickDown",
    "GamepadRStickLeft", "GamepadRStickRight", "GamepadRStickUp", "GamepadRStickDown",
    "MouseLeft", "MouseRight", "MouseMiddle", "MouseX1", "MouseX2", "MouseWheelX", "MouseWheelY",
    "ModCtrl", "ModShift", "ModAlt", "ModSuper", // ReservedForModXXX are showing the ModXXX names.
};
IM_STATIC_ASSERT(ImGuiKey_NamedKey_COUNT == IM_ARRAYSIZE(GKeyNames));

const char* ImGui::GetKeyName(ImGuiKey key)
{
    ImGuiContext& g = *GImGui;
#ifdef IMGUI_DISABLE_OBSOLETE_KEYIO
    IM_ASSERT((IsNamedKeyOrModKey(key) || key == ImGuiKey_None) && "Support for user key indices was dropped in favor of ImGuiKey. Please update backend and user code.");
#else
    if (IsLegacyKey(key))
    {
        if (g.IO.KeyMap[key] == -1)
            return "N/A";
        IM_ASSERT(IsNamedKey((ImGuiKey)g.IO.KeyMap[key]));
        key = (ImGuiKey)g.IO.KeyMap[key];
    }
#endif
    if (key == ImGuiKey_None)
        return "None";
    if (key & ImGuiMod_Mask_)
        key = ConvertSingleModFlagToKey(&g, key);
    if (!IsNamedKey(key))
        return "Unknown";

    return GKeyNames[key - ImGuiKey_NamedKey_BEGIN];
}

// ImGuiMod_Shortcut is translated to either Ctrl or Super.
void ImGui::GetKeyChordName(ImGuiKeyChord key_chord, char* out_buf, int out_buf_size)
{
    ImGuiContext& g = *GImGui;
    if (key_chord & ImGuiMod_Shortcut)
        key_chord = ConvertShortcutMod(key_chord);
    ImFormatString(out_buf, (size_t)out_buf_size, "%s%s%s%s%s",
        (key_chord & ImGuiMod_Ctrl) ? "Ctrl+" : "",
        (key_chord & ImGuiMod_Shift) ? "Shift+" : "",
        (key_chord & ImGuiMod_Alt) ? "Alt+" : "",
        (key_chord & ImGuiMod_Super) ? (g.IO.ConfigMacOSXBehaviors ? "Cmd+" : "Super+") : "",
        GetKeyName((ImGuiKey)(key_chord & ~ImGuiMod_Mask_)));
}

// t0 = previous time (e.g.: g.Time - g.IO.DeltaTime)
// t1 = current time (e.g.: g.Time)
// An event is triggered at:
//  t = 0.0f     t = repeat_delay,    t = repeat_delay + repeat_rate*N
int ImGui::CalcTypematicRepeatAmount(float t0, float t1, float repeat_delay, float repeat_rate)
{
    if (t1 == 0.0f)
        return 1;
    if (t0 >= t1)
        return 0;
    if (repeat_rate <= 0.0f)
        return (t0 < repeat_delay) && (t1 >= repeat_delay);
    const int count_t0 = (t0 < repeat_delay) ? -1 : (int)((t0 - repeat_delay) / repeat_rate);
    const int count_t1 = (t1 < repeat_delay) ? -1 : (int)((t1 - repeat_delay) / repeat_rate);
    const int count = count_t1 - count_t0;
    return count;
}

void ImGui::GetTypematicRepeatRate(ImGuiInputFlags flags, float* repeat_delay, float* repeat_rate)
{
    ImGuiContext& g = *GImGui;
    switch (flags & ImGuiInputFlags_RepeatRateMask_)
    {
    case ImGuiInputFlags_RepeatRateNavMove:             *repeat_delay = g.IO.KeyRepeatDelay * 0.72f; *repeat_rate = g.IO.KeyRepeatRate * 0.80f; return;
    case ImGuiInputFlags_RepeatRateNavTweak:            *repeat_delay = g.IO.KeyRepeatDelay * 0.72f; *repeat_rate = g.IO.KeyRepeatRate * 0.30f; return;
    case ImGuiInputFlags_RepeatRateDefault: default:    *repeat_delay = g.IO.KeyRepeatDelay * 1.00f; *repeat_rate = g.IO.KeyRepeatRate * 1.00f; return;
    }
}

// Return value representing the number of presses in the last time period, for the given repeat rate
// (most often returns 0 or 1. The result is generally only >1 when RepeatRate is smaller than DeltaTime, aka large DeltaTime or fast RepeatRate)
int ImGui::GetKeyPressedAmount(ImGuiKey key, float repeat_delay, float repeat_rate)
{
    ImGuiContext& g = *GImGui;
    const ImGuiKeyData* key_data = GetKeyData(key);
    if (!key_data->Down) // In theory this should already be encoded as (DownDuration < 0.0f), but testing this facilitates eating mechanism (until we finish work on key ownership)
        return 0;
    const float t = key_data->DownDuration;
    return CalcTypematicRepeatAmount(t - g.IO.DeltaTime, t, repeat_delay, repeat_rate);
}

// Return 2D vector representing the combination of four cardinal direction, with analog value support (for e.g. ImGuiKey_GamepadLStick* values).
ImVec2 ImGui::GetKeyMagnitude2d(ImGuiKey key_left, ImGuiKey key_right, ImGuiKey key_up, ImGuiKey key_down)
{
    return ImVec2(
        GetKeyData(key_right)->AnalogValue - GetKeyData(key_left)->AnalogValue,
        GetKeyData(key_down)->AnalogValue - GetKeyData(key_up)->AnalogValue);
}

// Rewrite routing data buffers to strip old entries + sort by key to make queries not touch scattered data.
//   Entries   D,A,B,B,A,C,B     --> A,A,B,B,B,C,D
//   Index     A:1 B:2 C:5 D:0   --> A:0 B:2 C:5 D:6
// See 'Metrics->Key Owners & Shortcut Routing' to visualize the result of that operation.
static void ImGui::UpdateKeyRoutingTable(ImGuiKeyRoutingTable* rt)
{
    ImGuiContext& g = *GImGui;
    rt->EntriesNext.resize(0);
    for (ImGuiKey key = ImGuiKey_NamedKey_BEGIN; key < ImGuiKey_NamedKey_END; key = (ImGuiKey)(key + 1))
    {
        const int new_routing_start_idx = rt->EntriesNext.Size;
        ImGuiKeyRoutingData* routing_entry;
        for (int old_routing_idx = rt->Index[key - ImGuiKey_NamedKey_BEGIN]; old_routing_idx != -1; old_routing_idx = routing_entry->NextEntryIndex)
        {
            routing_entry = &rt->Entries[old_routing_idx];
            routing_entry->RoutingCurr = routing_entry->RoutingNext; // Update entry
            routing_entry->RoutingNext = ImGuiKeyOwner_None;
            routing_entry->RoutingNextScore = 255;
            if (routing_entry->RoutingCurr == ImGuiKeyOwner_None)
                continue;
            rt->EntriesNext.push_back(*routing_entry); // Write alive ones into new buffer

            // Apply routing to owner if there's no owner already (RoutingCurr == None at this point)
            if (routing_entry->Mods == g.IO.KeyMods)
            {
                ImGuiKeyOwnerData* owner_data = GetKeyOwnerData(&g, key);
                if (owner_data->OwnerCurr == ImGuiKeyOwner_None)
                    owner_data->OwnerCurr = routing_entry->RoutingCurr;
            }
        }

        // Rewrite linked-list
        rt->Index[key - ImGuiKey_NamedKey_BEGIN] = (ImGuiKeyRoutingIndex)(new_routing_start_idx < rt->EntriesNext.Size ? new_routing_start_idx : -1);
        for (int n = new_routing_start_idx; n < rt->EntriesNext.Size; n++)
            rt->EntriesNext[n].NextEntryIndex = (ImGuiKeyRoutingIndex)((n + 1 < rt->EntriesNext.Size) ? n + 1 : -1);
    }
    rt->Entries.swap(rt->EntriesNext); // Swap new and old indexes
}

// owner_id may be None/Any, but routing_id needs to be always be set, so we default to GetCurrentFocusScope().
static inline ImGuiID GetRoutingIdFromOwnerId(ImGuiID owner_id)
{
    ImGuiContext& g = *GImGui;
    return (owner_id != ImGuiKeyOwner_None && owner_id != ImGuiKeyOwner_Any) ? owner_id : g.CurrentFocusScopeId;
}

ImGuiKeyRoutingData* ImGui::GetShortcutRoutingData(ImGuiKeyChord key_chord)
{
    // Majority of shortcuts will be Key + any number of Mods
    // We accept _Single_ mod with ImGuiKey_None.
    //  - Shortcut(ImGuiKey_S | ImGuiMod_Ctrl);                    // Legal
    //  - Shortcut(ImGuiKey_S | ImGuiMod_Ctrl | ImGuiMod_Shift);   // Legal
    //  - Shortcut(ImGuiMod_Ctrl);                                 // Legal
    //  - Shortcut(ImGuiMod_Ctrl | ImGuiMod_Shift);                // Not legal
    ImGuiContext& g = *GImGui;
    ImGuiKeyRoutingTable* rt = &g.KeysRoutingTable;
    ImGuiKeyRoutingData* routing_data;
    if (key_chord & ImGuiMod_Shortcut)
        key_chord = ConvertShortcutMod(key_chord);
    ImGuiKey key = (ImGuiKey)(key_chord & ~ImGuiMod_Mask_);
    ImGuiKey mods = (ImGuiKey)(key_chord & ImGuiMod_Mask_);
    if (key == ImGuiKey_None)
        key = ConvertSingleModFlagToKey(&g, mods);
    IM_ASSERT(IsNamedKey(key));

    // Get (in the majority of case, the linked list will have one element so this should be 2 reads.
    // Subsequent elements will be contiguous in memory as list is sorted/rebuilt in NewFrame).
    for (ImGuiKeyRoutingIndex idx = rt->Index[key - ImGuiKey_NamedKey_BEGIN]; idx != -1; idx = routing_data->NextEntryIndex)
    {
        routing_data = &rt->Entries[idx];
        if (routing_data->Mods == mods)
            return routing_data;
    }

    // Add to linked-list
    ImGuiKeyRoutingIndex routing_data_idx = (ImGuiKeyRoutingIndex)rt->Entries.Size;
    rt->Entries.push_back(ImGuiKeyRoutingData());
    routing_data = &rt->Entries[routing_data_idx];
    routing_data->Mods = (ImU16)mods;
    routing_data->NextEntryIndex = rt->Index[key - ImGuiKey_NamedKey_BEGIN]; // Setup linked list
    rt->Index[key - ImGuiKey_NamedKey_BEGIN] = routing_data_idx;
    return routing_data;
}

// Current score encoding (lower is highest priority):
//  -   0: ImGuiInputFlags_RouteGlobalHigh
//  -   1: ImGuiInputFlags_RouteFocused (if item active)
//  -   2: ImGuiInputFlags_RouteGlobal
//  -  3+: ImGuiInputFlags_RouteFocused (if window in focus-stack)
//  - 254: ImGuiInputFlags_RouteGlobalLow
//  - 255: never route
// 'flags' should include an explicit routing policy
static int CalcRoutingScore(ImGuiWindow* location, ImGuiID owner_id, ImGuiInputFlags flags)
{
    if (flags & ImGuiInputFlags_RouteFocused)
    {
        ImGuiContext& g = *GImGui;
        ImGuiWindow* focused = g.NavWindow;

        // ActiveID gets top priority
        // (we don't check g.ActiveIdUsingAllKeys here. Routing is applied but if input ownership is tested later it may discard it)
        if (owner_id != 0 && g.ActiveId == owner_id)
            return 1;

        // Score based on distance to focused window (lower is better)
        // Assuming both windows are submitting a routing request,
        // - When Window....... is focused -> Window scores 3 (best), Window/ChildB scores 255 (no match)
        // - When Window/ChildB is focused -> Window scores 4,        Window/ChildB scores 3 (best)
        // Assuming only WindowA is submitting a routing request,
        // - When Window/ChildB is focused -> Window scores 4 (best), Window/ChildB doesn't have a score.
        if (focused != NULL && focused->RootWindow == location->RootWindow)
            for (int next_score = 3; focused != NULL; next_score++)
            {
                if (focused == location)
                {
                    IM_ASSERT(next_score < 255);
                    return next_score;
                }
                focused = (focused->RootWindow != focused) ? focused->ParentWindow : NULL; // FIXME: This could be later abstracted as a focus path
            }
        return 255;
    }

    // ImGuiInputFlags_RouteGlobalHigh is default, so calls without flags are not conditional
    if (flags & ImGuiInputFlags_RouteGlobal)
        return 2;
    if (flags & ImGuiInputFlags_RouteGlobalLow)
        return 254;
    return 0;
}

// Request a desired route for an input chord (key + mods).
// Return true if the route is available this frame.
// - Routes and key ownership are attributed at the beginning of next frame based on best score and mod state.
//   (Conceptually this does a "Submit for next frame" + "Test for current frame".
//   As such, it could be called TrySetXXX or SubmitXXX, or the Submit and Test operations should be separate.)
// - Using 'owner_id == ImGuiKeyOwner_Any/0': auto-assign an owner based on current focus scope (each window has its focus scope by default)
// - Using 'owner_id == ImGuiKeyOwner_None': allows disabling/locking a shortcut.
bool ImGui::SetShortcutRouting(ImGuiKeyChord key_chord, ImGuiID owner_id, ImGuiInputFlags flags)
{
    ImGuiContext& g = *GImGui;
    if ((flags & ImGuiInputFlags_RouteMask_) == 0)
        flags |= ImGuiInputFlags_RouteGlobalHigh; // IMPORTANT: This is the default for SetShortcutRouting() but NOT Shortcut()
    else
        IM_ASSERT(ImIsPowerOfTwo(flags & ImGuiInputFlags_RouteMask_)); // Check that only 1 routing flag is used

    if (flags & ImGuiInputFlags_RouteUnlessBgFocused)
        if (g.NavWindow == NULL)
            return false;
    if (flags & ImGuiInputFlags_RouteAlways)
        return true;

    const int score = CalcRoutingScore(g.CurrentWindow, owner_id, flags);
    if (score == 255)
        return false;

    // Submit routing for NEXT frame (assuming score is sufficient)
    // FIXME: Could expose a way to use a "serve last" policy for same score resolution (using <= instead of <).
    ImGuiKeyRoutingData* routing_data = GetShortcutRoutingData(key_chord);
    const ImGuiID routing_id = GetRoutingIdFromOwnerId(owner_id);
    //const bool set_route = (flags & ImGuiInputFlags_ServeLast) ? (score <= routing_data->RoutingNextScore) : (score < routing_data->RoutingNextScore);
    if (score < routing_data->RoutingNextScore)
    {
        routing_data->RoutingNext = routing_id;
        routing_data->RoutingNextScore = (ImU8)score;
    }

    // Return routing state for CURRENT frame
    return routing_data->RoutingCurr == routing_id;
}

// Currently unused by core (but used by tests)
// Note: this cannot be turned into GetShortcutRouting() because we do the owner_id->routing_id translation, name would be more misleading.
bool ImGui::TestShortcutRouting(ImGuiKeyChord key_chord, ImGuiID owner_id)
{
    const ImGuiID routing_id = GetRoutingIdFromOwnerId(owner_id);
    ImGuiKeyRoutingData* routing_data = GetShortcutRoutingData(key_chord); // FIXME: Could avoid creating entry.
    return routing_data->RoutingCurr == routing_id;
}

// Note that Dear ImGui doesn't know the meaning/semantic of ImGuiKey from 0..511: they are legacy native keycodes.
// Consider transitioning from 'IsKeyDown(MY_ENGINE_KEY_A)' (<1.87) to IsKeyDown(ImGuiKey_A) (>= 1.87)
bool ImGui::IsKeyDown(ImGuiKey key)
{
    return IsKeyDown(key, ImGuiKeyOwner_Any);
}

bool ImGui::IsKeyDown(ImGuiKey key, ImGuiID owner_id)
{
    const ImGuiKeyData* key_data = GetKeyData(key);
    if (!key_data->Down)
        return false;
    if (!TestKeyOwner(key, owner_id))
        return false;
    return true;
}

bool ImGui::IsKeyPressed(ImGuiKey key, bool repeat)
{
    return IsKeyPressed(key, ImGuiKeyOwner_Any, repeat ? ImGuiInputFlags_Repeat : ImGuiInputFlags_None);
}

// Important: unless legacy IsKeyPressed(ImGuiKey, bool repeat=true) which DEFAULT to repeat, this requires EXPLICIT repeat.
bool ImGui::IsKeyPressed(ImGuiKey key, ImGuiID owner_id, ImGuiInputFlags flags)
{
    const ImGuiKeyData* key_data = GetKeyData(key);
    if (!key_data->Down) // In theory this should already be encoded as (DownDuration < 0.0f), but testing this facilitates eating mechanism (until we finish work on key ownership)
        return false;
    const float t = key_data->DownDuration;
    if (t < 0.0f)
        return false;
    IM_ASSERT((flags & ~ImGuiInputFlags_SupportedByIsKeyPressed) == 0); // Passing flags not supported by this function!

    bool pressed = (t == 0.0f);
    if (!pressed && ((flags & ImGuiInputFlags_Repeat) != 0))
    {
        float repeat_delay, repeat_rate;
        GetTypematicRepeatRate(flags, &repeat_delay, &repeat_rate);
        pressed = (t > repeat_delay) && GetKeyPressedAmount(key, repeat_delay, repeat_rate) > 0;
    }
    if (!pressed)
        return false;
    if (!TestKeyOwner(key, owner_id))
        return false;
    return true;
}

bool ImGui::IsKeyReleased(ImGuiKey key)
{
    return IsKeyReleased(key, ImGuiKeyOwner_Any);
}

bool ImGui::IsKeyReleased(ImGuiKey key, ImGuiID owner_id)
{
    const ImGuiKeyData* key_data = GetKeyData(key);
    if (key_data->DownDurationPrev < 0.0f || key_data->Down)
        return false;
    if (!TestKeyOwner(key, owner_id))
        return false;
    return true;
}

bool ImGui::IsMouseDown(ImGuiMouseButton button)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(button >= 0 && button < IM_ARRAYSIZE(g.IO.MouseDown));
    return g.IO.MouseDown[button] && TestKeyOwner(MouseButtonToKey(button), ImGuiKeyOwner_Any); // should be same as IsKeyDown(MouseButtonToKey(button), ImGuiKeyOwner_Any), but this allows legacy code hijacking the io.Mousedown[] array.
}

bool ImGui::IsMouseDown(ImGuiMouseButton button, ImGuiID owner_id)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(button >= 0 && button < IM_ARRAYSIZE(g.IO.MouseDown));
    return g.IO.MouseDown[button] && TestKeyOwner(MouseButtonToKey(button), owner_id); // Should be same as IsKeyDown(MouseButtonToKey(button), owner_id), but this allows legacy code hijacking the io.Mousedown[] array.
}

bool ImGui::IsMouseClicked(ImGuiMouseButton button, bool repeat)
{
    return IsMouseClicked(button, ImGuiKeyOwner_Any, repeat ? ImGuiInputFlags_Repeat : ImGuiInputFlags_None);
}

bool ImGui::IsMouseClicked(ImGuiMouseButton button, ImGuiID owner_id, ImGuiInputFlags flags)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(button >= 0 && button < IM_ARRAYSIZE(g.IO.MouseDown));
    if (!g.IO.MouseDown[button]) // In theory this should already be encoded as (DownDuration < 0.0f), but testing this facilitates eating mechanism (until we finish work on key ownership)
        return false;
    const float t = g.IO.MouseDownDuration[button];
    if (t < 0.0f)
        return false;
    IM_ASSERT((flags & ~ImGuiInputFlags_SupportedByIsKeyPressed) == 0); // Passing flags not supported by this function!

    const bool repeat = (flags & ImGuiInputFlags_Repeat) != 0;
    const bool pressed = (t == 0.0f) || (repeat && t > g.IO.KeyRepeatDelay && CalcTypematicRepeatAmount(t - g.IO.DeltaTime, t, g.IO.KeyRepeatDelay, g.IO.KeyRepeatRate) > 0);
    if (!pressed)
        return false;

    if (!TestKeyOwner(MouseButtonToKey(button), owner_id))
        return false;

    return true;
}

bool ImGui::IsMouseReleased(ImGuiMouseButton button)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(button >= 0 && button < IM_ARRAYSIZE(g.IO.MouseDown));
    return g.IO.MouseReleased[button] && TestKeyOwner(MouseButtonToKey(button), ImGuiKeyOwner_Any); // Should be same as IsKeyReleased(MouseButtonToKey(button), ImGuiKeyOwner_Any)
}

bool ImGui::IsMouseReleased(ImGuiMouseButton button, ImGuiID owner_id)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(button >= 0 && button < IM_ARRAYSIZE(g.IO.MouseDown));
    return g.IO.MouseReleased[button] && TestKeyOwner(MouseButtonToKey(button), owner_id); // Should be same as IsKeyReleased(MouseButtonToKey(button), owner_id)
}

bool ImGui::IsMouseDoubleClicked(ImGuiMouseButton button)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(button >= 0 && button < IM_ARRAYSIZE(g.IO.MouseDown));
    return g.IO.MouseClickedCount[button] == 2 && TestKeyOwner(MouseButtonToKey(button), ImGuiKeyOwner_Any);
}

bool ImGui::IsMouseDoubleClicked(ImGuiMouseButton button, ImGuiID owner_id)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(button >= 0 && button < IM_ARRAYSIZE(g.IO.MouseDown));
    return g.IO.MouseClickedCount[button] == 2 && TestKeyOwner(MouseButtonToKey(button), owner_id);
}

int ImGui::GetMouseClickedCount(ImGuiMouseButton button)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(button >= 0 && button < IM_ARRAYSIZE(g.IO.MouseDown));
    return g.IO.MouseClickedCount[button];
}

// Test if mouse cursor is hovering given rectangle
// NB- Rectangle is clipped by our current clip setting
// NB- Expand the rectangle to be generous on imprecise inputs systems (g.Style.TouchExtraPadding)
bool ImGui::IsMouseHoveringRect(const ImVec2& r_min, const ImVec2& r_max, bool clip)
{
    ImGuiContext& g = *GImGui;

    // Clip
    ImRect rect_clipped(r_min, r_max);
    if (clip)
        rect_clipped.ClipWith(g.CurrentWindow->ClipRect);

    // Hit testing, expanded for touch input
    if (!rect_clipped.ContainsWithPad(g.IO.MousePos, g.Style.TouchExtraPadding))
        return false;
    if (!g.MouseViewport->GetMainRect().Overlaps(rect_clipped))
        return false;
    return true;
}

// Return if a mouse click/drag went past the given threshold. Valid to call during the MouseReleased frame.
// [Internal] This doesn't test if the button is pressed
bool ImGui::IsMouseDragPastThreshold(ImGuiMouseButton button, float lock_threshold)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(button >= 0 && button < IM_ARRAYSIZE(g.IO.MouseDown));
    if (lock_threshold < 0.0f)
        lock_threshold = g.IO.MouseDragThreshold;
    return g.IO.MouseDragMaxDistanceSqr[button] >= lock_threshold * lock_threshold;
}

bool ImGui::IsMouseDragging(ImGuiMouseButton button, float lock_threshold)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(button >= 0 && button < IM_ARRAYSIZE(g.IO.MouseDown));
    if (!g.IO.MouseDown[button])
        return false;
    return IsMouseDragPastThreshold(button, lock_threshold);
}

ImVec2 ImGui::GetMousePos()
{
    ImGuiContext& g = *GImGui;
    return g.IO.MousePos;
}

// This is called TeleportMousePos() and not SetMousePos() to emphasis that setting MousePosPrev will effectively clear mouse delta as well.
// It is expected you only call this if (io.BackendFlags & ImGuiBackendFlags_HasSetMousePos) is set and supported by backend.
void ImGui::TeleportMousePos(const ImVec2& pos)
{
    ImGuiContext& g = *GImGui;
    g.IO.MousePos = g.IO.MousePosPrev = pos;
    g.IO.MouseDelta = ImVec2(0.0f, 0.0f);
    g.IO.WantSetMousePos = true;
    //IMGUI_DEBUG_LOG_IO("TeleportMousePos: (%.1f,%.1f)\n", io.MousePos.x, io.MousePos.y);
}

// NB: prefer to call right after BeginPopup(). At the time Selectable/MenuItem is activated, the popup is already closed!
ImVec2 ImGui::GetMousePosOnOpeningCurrentPopup()
{
    ImGuiContext& g = *GImGui;
    if (g.BeginPopupStack.Size > 0)
        return g.OpenPopupStack[g.BeginPopupStack.Size - 1].OpenMousePos;
    return g.IO.MousePos;
}

// We typically use ImVec2(-FLT_MAX,-FLT_MAX) to denote an invalid mouse position.
bool ImGui::IsMousePosValid(const ImVec2* mouse_pos)
{
    // The assert is only to silence a false-positive in XCode Static Analysis.
    // Because GImGui is not dereferenced in every code path, the static analyzer assume that it may be NULL (which it doesn't for other functions).
    IM_ASSERT(GImGui != NULL);
    const float MOUSE_INVALID = -256000.0f;
    ImVec2 p = mouse_pos ? *mouse_pos : GImGui->IO.MousePos;
    return p.x >= MOUSE_INVALID && p.y >= MOUSE_INVALID;
}

// [WILL OBSOLETE] This was designed for backends, but prefer having backend maintain a mask of held mouse buttons, because upcoming input queue system will make this invalid.
bool ImGui::IsAnyMouseDown()
{
    ImGuiContext& g = *GImGui;
    for (int n = 0; n < IM_ARRAYSIZE(g.IO.MouseDown); n++)
        if (g.IO.MouseDown[n])
            return true;
    return false;
}

// Return the delta from the initial clicking position while the mouse button is clicked or was just released.
// This is locked and return 0.0f until the mouse moves past a distance threshold at least once.
// NB: This is only valid if IsMousePosValid(). backends in theory should always keep mouse position valid when dragging even outside the client window.
ImVec2 ImGui::GetMouseDragDelta(ImGuiMouseButton button, float lock_threshold)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(button >= 0 && button < IM_ARRAYSIZE(g.IO.MouseDown));
    if (lock_threshold < 0.0f)
        lock_threshold = g.IO.MouseDragThreshold;
    if (g.IO.MouseDown[button] || g.IO.MouseReleased[button])
        if (g.IO.MouseDragMaxDistanceSqr[button] >= lock_threshold * lock_threshold)
            if (IsMousePosValid(&g.IO.MousePos) && IsMousePosValid(&g.IO.MouseClickedPos[button]))
                return g.IO.MousePos - g.IO.MouseClickedPos[button];
    return ImVec2(0.0f, 0.0f);
}

void ImGui::ResetMouseDragDelta(ImGuiMouseButton button)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(button >= 0 && button < IM_ARRAYSIZE(g.IO.MouseDown));
    // NB: We don't need to reset g.IO.MouseDragMaxDistanceSqr
    g.IO.MouseClickedPos[button] = g.IO.MousePos;
}

// Get desired mouse cursor shape.
// Important: this is meant to be used by a platform backend, it is reset in ImGui::NewFrame(),
// updated during the frame, and locked in EndFrame()/Render().
// If you use software rendering by setting io.MouseDrawCursor then Dear ImGui will render those for you
ImGuiMouseCursor ImGui::GetMouseCursor()
{
    ImGuiContext& g = *GImGui;
    return g.MouseCursor;
}

void ImGui::SetMouseCursor(ImGuiMouseCursor cursor_type)
{
    ImGuiContext& g = *GImGui;
    g.MouseCursor = cursor_type;
}

static void UpdateAliasKey(ImGuiKey key, bool v, float analog_value)
{
    IM_ASSERT(ImGui::IsAliasKey(key));
    ImGuiKeyData* key_data = ImGui::GetKeyData(key);
    key_data->Down = v;
    key_data->AnalogValue = analog_value;
}

// [Internal] Do not use directly
static ImGuiKeyChord GetMergedModsFromKeys()
{
    ImGuiKeyChord mods = 0;
    if (ImGui::IsKeyDown(ImGuiMod_Ctrl))     { mods |= ImGuiMod_Ctrl; }
    if (ImGui::IsKeyDown(ImGuiMod_Shift))    { mods |= ImGuiMod_Shift; }
    if (ImGui::IsKeyDown(ImGuiMod_Alt))      { mods |= ImGuiMod_Alt; }
    if (ImGui::IsKeyDown(ImGuiMod_Super))    { mods |= ImGuiMod_Super; }
    return mods;
}

static void ImGui::UpdateKeyboardInputs()
{
    ImGuiContext& g = *GImGui;
    ImGuiIO& io = g.IO;

    // Import legacy keys or verify they are not used
#ifndef IMGUI_DISABLE_OBSOLETE_KEYIO
    if (io.BackendUsingLegacyKeyArrays == 0)
    {
        // Backend used new io.AddKeyEvent() API: Good! Verify that old arrays are never written to externally.
        for (int n = 0; n < ImGuiKey_LegacyNativeKey_END; n++)
            IM_ASSERT((io.KeysDown[n] == false || IsKeyDown((ImGuiKey)n)) && "Backend needs to either only use io.AddKeyEvent(), either only fill legacy io.KeysDown[] + io.KeyMap[]. Not both!");
    }
    else
    {
        if (g.FrameCount == 0)
            for (int n = ImGuiKey_LegacyNativeKey_BEGIN; n < ImGuiKey_LegacyNativeKey_END; n++)
                IM_ASSERT(g.IO.KeyMap[n] == -1 && "Backend is not allowed to write to io.KeyMap[0..511]!");

        // Build reverse KeyMap (Named -> Legacy)
        for (int n = ImGuiKey_NamedKey_BEGIN; n < ImGuiKey_NamedKey_END; n++)
            if (io.KeyMap[n] != -1)
            {
                IM_ASSERT(IsLegacyKey((ImGuiKey)io.KeyMap[n]));
                io.KeyMap[io.KeyMap[n]] = n;
            }

        // Import legacy keys into new ones
        for (int n = ImGuiKey_LegacyNativeKey_BEGIN; n < ImGuiKey_LegacyNativeKey_END; n++)
            if (io.KeysDown[n] || io.BackendUsingLegacyKeyArrays == 1)
            {
                const ImGuiKey key = (ImGuiKey)(io.KeyMap[n] != -1 ? io.KeyMap[n] : n);
                IM_ASSERT(io.KeyMap[n] == -1 || IsNamedKey(key));
                io.KeysData[key].Down = io.KeysDown[n];
                if (key != n)
                    io.KeysDown[key] = io.KeysDown[n]; // Allow legacy code using io.KeysDown[GetKeyIndex()] with old backends
                io.BackendUsingLegacyKeyArrays = 1;
            }
        if (io.BackendUsingLegacyKeyArrays == 1)
        {
            GetKeyData(ImGuiMod_Ctrl)->Down = io.KeyCtrl;
            GetKeyData(ImGuiMod_Shift)->Down = io.KeyShift;
            GetKeyData(ImGuiMod_Alt)->Down = io.KeyAlt;
            GetKeyData(ImGuiMod_Super)->Down = io.KeySuper;
        }
    }

#ifndef IMGUI_DISABLE_OBSOLETE_KEYIO
    const bool nav_gamepad_active = (io.ConfigFlags & ImGuiConfigFlags_NavEnableGamepad) != 0 && (io.BackendFlags & ImGuiBackendFlags_HasGamepad) != 0;
    if (io.BackendUsingLegacyNavInputArray && nav_gamepad_active)
    {
        #define MAP_LEGACY_NAV_INPUT_TO_KEY1(_KEY, _NAV1)           do { io.KeysData[_KEY].Down = (io.NavInputs[_NAV1] > 0.0f); io.KeysData[_KEY].AnalogValue = io.NavInputs[_NAV1]; } while (0)
        #define MAP_LEGACY_NAV_INPUT_TO_KEY2(_KEY, _NAV1, _NAV2)    do { io.KeysData[_KEY].Down = (io.NavInputs[_NAV1] > 0.0f) || (io.NavInputs[_NAV2] > 0.0f); io.KeysData[_KEY].AnalogValue = ImMax(io.NavInputs[_NAV1], io.NavInputs[_NAV2]); } while (0)
        MAP_LEGACY_NAV_INPUT_TO_KEY1(ImGuiKey_GamepadFaceDown, ImGuiNavInput_Activate);
        MAP_LEGACY_NAV_INPUT_TO_KEY1(ImGuiKey_GamepadFaceRight, ImGuiNavInput_Cancel);
        MAP_LEGACY_NAV_INPUT_TO_KEY1(ImGuiKey_GamepadFaceLeft, ImGuiNavInput_Menu);
        MAP_LEGACY_NAV_INPUT_TO_KEY1(ImGuiKey_GamepadFaceUp, ImGuiNavInput_Input);
        MAP_LEGACY_NAV_INPUT_TO_KEY1(ImGuiKey_GamepadDpadLeft, ImGuiNavInput_DpadLeft);
        MAP_LEGACY_NAV_INPUT_TO_KEY1(ImGuiKey_GamepadDpadRight, ImGuiNavInput_DpadRight);
        MAP_LEGACY_NAV_INPUT_TO_KEY1(ImGuiKey_GamepadDpadUp, ImGuiNavInput_DpadUp);
        MAP_LEGACY_NAV_INPUT_TO_KEY1(ImGuiKey_GamepadDpadDown, ImGuiNavInput_DpadDown);
        MAP_LEGACY_NAV_INPUT_TO_KEY2(ImGuiKey_GamepadL1, ImGuiNavInput_FocusPrev, ImGuiNavInput_TweakSlow);
        MAP_LEGACY_NAV_INPUT_TO_KEY2(ImGuiKey_GamepadR1, ImGuiNavInput_FocusNext, ImGuiNavInput_TweakFast);
        MAP_LEGACY_NAV_INPUT_TO_KEY1(ImGuiKey_GamepadLStickLeft, ImGuiNavInput_LStickLeft);
        MAP_LEGACY_NAV_INPUT_TO_KEY1(ImGuiKey_GamepadLStickRight, ImGuiNavInput_LStickRight);
        MAP_LEGACY_NAV_INPUT_TO_KEY1(ImGuiKey_GamepadLStickUp, ImGuiNavInput_LStickUp);
        MAP_LEGACY_NAV_INPUT_TO_KEY1(ImGuiKey_GamepadLStickDown, ImGuiNavInput_LStickDown);
        #undef NAV_MAP_KEY
    }
#endif
#endif

    // Update aliases
    for (int n = 0; n < ImGuiMouseButton_COUNT; n++)
        UpdateAliasKey(MouseButtonToKey(n), io.MouseDown[n], io.MouseDown[n] ? 1.0f : 0.0f);
    UpdateAliasKey(ImGuiKey_MouseWheelX, io.MouseWheelH != 0.0f, io.MouseWheelH);
    UpdateAliasKey(ImGuiKey_MouseWheelY, io.MouseWheel != 0.0f, io.MouseWheel);

    // Synchronize io.KeyMods and io.KeyXXX values.
    // - New backends (1.87+): send io.AddKeyEvent(ImGuiMod_XXX) ->                                      -> (here) deriving io.KeyMods + io.KeyXXX from key array.
    // - Legacy backends:      set io.KeyXXX bools               -> (above) set key array from io.KeyXXX -> (here) deriving io.KeyMods + io.KeyXXX from key array.
    // So with legacy backends the 4 values will do a unnecessary back-and-forth but it makes the code simpler and future facing.
    io.KeyMods = GetMergedModsFromKeys();
    io.KeyCtrl = (io.KeyMods & ImGuiMod_Ctrl) != 0;
    io.KeyShift = (io.KeyMods & ImGuiMod_Shift) != 0;
    io.KeyAlt = (io.KeyMods & ImGuiMod_Alt) != 0;
    io.KeySuper = (io.KeyMods & ImGuiMod_Super) != 0;

    // Clear gamepad data if disabled
    if ((io.BackendFlags & ImGuiBackendFlags_HasGamepad) == 0)
        for (int i = ImGuiKey_Gamepad_BEGIN; i < ImGuiKey_Gamepad_END; i++)
        {
            io.KeysData[i - ImGuiKey_KeysData_OFFSET].Down = false;
            io.KeysData[i - ImGuiKey_KeysData_OFFSET].AnalogValue = 0.0f;
        }

    // Update keys
    for (int i = 0; i < ImGuiKey_KeysData_SIZE; i++)
    {
        ImGuiKeyData* key_data = &io.KeysData[i];
        key_data->DownDurationPrev = key_data->DownDuration;
        key_data->DownDuration = key_data->Down ? (key_data->DownDuration < 0.0f ? 0.0f : key_data->DownDuration + io.DeltaTime) : -1.0f;
    }

    // Update keys/input owner (named keys only): one entry per key
    for (ImGuiKey key = ImGuiKey_NamedKey_BEGIN; key < ImGuiKey_NamedKey_END; key = (ImGuiKey)(key + 1))
    {
        ImGuiKeyData* key_data = &io.KeysData[key - ImGuiKey_KeysData_OFFSET];
        ImGuiKeyOwnerData* owner_data = &g.KeysOwnerData[key - ImGuiKey_NamedKey_BEGIN];
        owner_data->OwnerCurr = owner_data->OwnerNext;
        if (!key_data->Down) // Important: ownership is released on the frame after a release. Ensure a 'MouseDown -> CloseWindow -> MouseUp' chain doesn't lead to someone else seeing the MouseUp.
            owner_data->OwnerNext = ImGuiKeyOwner_None;
        owner_data->LockThisFrame = owner_data->LockUntilRelease = owner_data->LockUntilRelease && key_data->Down;  // Clear LockUntilRelease when key is not Down anymore
    }

    UpdateKeyRoutingTable(&g.KeysRoutingTable);
}

static void ImGui::UpdateMouseInputs()
{
    ImGuiContext& g = *GImGui;
    ImGuiIO& io = g.IO;

    // Mouse Wheel swapping flag
    // As a standard behavior holding SHIFT while using Vertical Mouse Wheel triggers Horizontal scroll instead
    // - We avoid doing it on OSX as it the OS input layer handles this already.
    // - FIXME: However this means when running on OSX over Emscripten, Shift+WheelY will incur two swapping (1 in OS, 1 here), canceling the feature.
    // - FIXME: When we can distinguish e.g. touchpad scroll events from mouse ones, we'll set this accordingly based on input source.
    io.MouseWheelRequestAxisSwap = io.KeyShift && !io.ConfigMacOSXBehaviors;

    // Round mouse position to avoid spreading non-rounded position (e.g. UpdateManualResize doesn't support them well)
    if (IsMousePosValid(&io.MousePos))
        io.MousePos = g.MouseLastValidPos = ImFloor(io.MousePos);

    // If mouse just appeared or disappeared (usually denoted by -FLT_MAX components) we cancel out movement in MouseDelta
    if (IsMousePosValid(&io.MousePos) && IsMousePosValid(&io.MousePosPrev))
        io.MouseDelta = io.MousePos - io.MousePosPrev;
    else
        io.MouseDelta = ImVec2(0.0f, 0.0f);

    // Update stationary timer.
    // FIXME: May need to rework again to have some tolerance for occasional small movement, while being functional on high-framerates.
    const float mouse_stationary_threshold = (io.MouseSource == ImGuiMouseSource_Mouse) ? 2.0f : 3.0f; // Slightly higher threshold for ImGuiMouseSource_TouchScreen/ImGuiMouseSource_Pen, may need rework.
    const bool mouse_stationary = (ImLengthSqr(io.MouseDelta) <= mouse_stationary_threshold * mouse_stationary_threshold);
    g.MouseStationaryTimer = mouse_stationary ? (g.MouseStationaryTimer + io.DeltaTime) : 0.0f;
    //IMGUI_DEBUG_LOG("%.4f\n", g.MouseStationaryTimer);

    // If mouse moved we re-enable mouse hovering in case it was disabled by gamepad/keyboard. In theory should use a >0.0f threshold but would need to reset in everywhere we set this to true.
    if (io.MouseDelta.x != 0.0f || io.MouseDelta.y != 0.0f)
        g.NavDisableMouseHover = false;

    for (int i = 0; i < IM_ARRAYSIZE(io.MouseDown); i++)
    {
        io.MouseClicked[i] = io.MouseDown[i] && io.MouseDownDuration[i] < 0.0f;
        io.MouseClickedCount[i] = 0; // Will be filled below
        io.MouseReleased[i] = !io.MouseDown[i] && io.MouseDownDuration[i] >= 0.0f;
        io.MouseDownDurationPrev[i] = io.MouseDownDuration[i];
        io.MouseDownDuration[i] = io.MouseDown[i] ? (io.MouseDownDuration[i] < 0.0f ? 0.0f : io.MouseDownDuration[i] + io.DeltaTime) : -1.0f;
        if (io.MouseClicked[i])
        {
            bool is_repeated_click = false;
            if ((float)(g.Time - io.MouseClickedTime[i]) < io.MouseDoubleClickTime)
            {
                ImVec2 delta_from_click_pos = IsMousePosValid(&io.MousePos) ? (io.MousePos - io.MouseClickedPos[i]) : ImVec2(0.0f, 0.0f);
                if (ImLengthSqr(delta_from_click_pos) < io.MouseDoubleClickMaxDist * io.MouseDoubleClickMaxDist)
                    is_repeated_click = true;
            }
            if (is_repeated_click)
                io.MouseClickedLastCount[i]++;
            else
                io.MouseClickedLastCount[i] = 1;
            io.MouseClickedTime[i] = g.Time;
            io.MouseClickedPos[i] = io.MousePos;
            io.MouseClickedCount[i] = io.MouseClickedLastCount[i];
            io.MouseDragMaxDistanceAbs[i] = ImVec2(0.0f, 0.0f);
            io.MouseDragMaxDistanceSqr[i] = 0.0f;
        }
        else if (io.MouseDown[i])
        {
            // Maintain the maximum distance we reaching from the initial click position, which is used with dragging threshold
            ImVec2 delta_from_click_pos = IsMousePosValid(&io.MousePos) ? (io.MousePos - io.MouseClickedPos[i]) : ImVec2(0.0f, 0.0f);
            io.MouseDragMaxDistanceSqr[i] = ImMax(io.MouseDragMaxDistanceSqr[i], ImLengthSqr(delta_from_click_pos));
            io.MouseDragMaxDistanceAbs[i].x = ImMax(io.MouseDragMaxDistanceAbs[i].x, delta_from_click_pos.x < 0.0f ? -delta_from_click_pos.x : delta_from_click_pos.x);
            io.MouseDragMaxDistanceAbs[i].y = ImMax(io.MouseDragMaxDistanceAbs[i].y, delta_from_click_pos.y < 0.0f ? -delta_from_click_pos.y : delta_from_click_pos.y);
        }

        // We provide io.MouseDoubleClicked[] as a legacy service
        io.MouseDoubleClicked[i] = (io.MouseClickedCount[i] == 2);

        // Clicking any mouse button reactivate mouse hovering which may have been deactivated by gamepad/keyboard navigation
        if (io.MouseClicked[i])
            g.NavDisableMouseHover = false;
    }
}

static void LockWheelingWindow(ImGuiWindow* window, float wheel_amount)
{
    ImGuiContext& g = *GImGui;
    if (window)
        g.WheelingWindowReleaseTimer = ImMin(g.WheelingWindowReleaseTimer + ImAbs(wheel_amount) * WINDOWS_MOUSE_WHEEL_SCROLL_LOCK_TIMER, WINDOWS_MOUSE_WHEEL_SCROLL_LOCK_TIMER);
    else
        g.WheelingWindowReleaseTimer = 0.0f;
    if (g.WheelingWindow == window)
        return;
    IMGUI_DEBUG_LOG_IO("[io] LockWheelingWindow() \"%s\"\n", window ? window->Name : "NULL");
    g.WheelingWindow = window;
    g.WheelingWindowRefMousePos = g.IO.MousePos;
    if (window == NULL)
    {
        g.WheelingWindowStartFrame = -1;
        g.WheelingAxisAvg = ImVec2(0.0f, 0.0f);
    }
}

static ImGuiWindow* FindBestWheelingWindow(const ImVec2& wheel)
{
    // For each axis, find window in the hierarchy that may want to use scrolling
    ImGuiContext& g = *GImGui;
    ImGuiWindow* windows[2] = { NULL, NULL };
    for (int axis = 0; axis < 2; axis++)
        if (wheel[axis] != 0.0f)
            for (ImGuiWindow* window = windows[axis] = g.HoveredWindow; window->Flags & ImGuiWindowFlags_ChildWindow; window = windows[axis] = window->ParentWindow)
            {
                // Bubble up into parent window if:
                // - a child window doesn't allow any scrolling.
                // - a child window has the ImGuiWindowFlags_NoScrollWithMouse flag.
                //// - a child window doesn't need scrolling because it is already at the edge for the direction we are going in (FIXME-WIP)
                const bool has_scrolling = (window->ScrollMax[axis] != 0.0f);
                const bool inputs_disabled = (window->Flags & ImGuiWindowFlags_NoScrollWithMouse) && !(window->Flags & ImGuiWindowFlags_NoMouseInputs);
                //const bool scrolling_past_limits = (wheel_v < 0.0f) ? (window->Scroll[axis] <= 0.0f) : (window->Scroll[axis] >= window->ScrollMax[axis]);
                if (has_scrolling && !inputs_disabled) // && !scrolling_past_limits)
                    break; // select this window
            }
    if (windows[0] == NULL && windows[1] == NULL)
        return NULL;

    // If there's only one window or only one axis then there's no ambiguity
    if (windows[0] == windows[1] || windows[0] == NULL || windows[1] == NULL)
        return windows[1] ? windows[1] : windows[0];

    // If candidate are different windows we need to decide which one to prioritize
    // - First frame: only find a winner if one axis is zero.
    // - Subsequent frames: only find a winner when one is more than the other.
    if (g.WheelingWindowStartFrame == -1)
        g.WheelingWindowStartFrame = g.FrameCount;
    if ((g.WheelingWindowStartFrame == g.FrameCount && wheel.x != 0.0f && wheel.y != 0.0f) || (g.WheelingAxisAvg.x == g.WheelingAxisAvg.y))
    {
        g.WheelingWindowWheelRemainder = wheel;
        return NULL;
    }
    return (g.WheelingAxisAvg.x > g.WheelingAxisAvg.y) ? windows[0] : windows[1];
}

// Called by NewFrame()
void ImGui::UpdateMouseWheel()
{
    // Reset the locked window if we move the mouse or after the timer elapses.
    // FIXME: Ideally we could refactor to have one timer for "changing window w/ same axis" and a shorter timer for "changing window or axis w/ other axis" (#3795)
    ImGuiContext& g = *GImGui;
    if (g.WheelingWindow != NULL)
    {
        g.WheelingWindowReleaseTimer -= g.IO.DeltaTime;
        if (IsMousePosValid() && ImLengthSqr(g.IO.MousePos - g.WheelingWindowRefMousePos) > g.IO.MouseDragThreshold * g.IO.MouseDragThreshold)
            g.WheelingWindowReleaseTimer = 0.0f;
        if (g.WheelingWindowReleaseTimer <= 0.0f)
            LockWheelingWindow(NULL, 0.0f);
    }

    ImVec2 wheel;
    wheel.x = TestKeyOwner(ImGuiKey_MouseWheelX, ImGuiKeyOwner_None) ? g.IO.MouseWheelH : 0.0f;
    wheel.y = TestKeyOwner(ImGuiKey_MouseWheelY, ImGuiKeyOwner_None) ? g.IO.MouseWheel : 0.0f;

    //IMGUI_DEBUG_LOG("MouseWheel X:%.3f Y:%.3f\n", wheel_x, wheel_y);
    ImGuiWindow* mouse_window = g.WheelingWindow ? g.WheelingWindow : g.HoveredWindow;
    if (!mouse_window || mouse_window->Collapsed)
        return;

    // Zoom / Scale window
    // FIXME-OBSOLETE: This is an old feature, it still works but pretty much nobody is using it and may be best redesigned.
    if (wheel.y != 0.0f && g.IO.KeyCtrl && g.IO.FontAllowUserScaling)
    {
        LockWheelingWindow(mouse_window, wheel.y);
        ImGuiWindow* window = mouse_window;
        const float new_font_scale = ImClamp(window->FontWindowScale + g.IO.MouseWheel * 0.10f, 0.50f, 2.50f);
        const float scale = new_font_scale / window->FontWindowScale;
        window->FontWindowScale = new_font_scale;
        if (window == window->RootWindow)
        {
            const ImVec2 offset = window->Size * (1.0f - scale) * (g.IO.MousePos - window->Pos) / window->Size;
            SetWindowPos(window, window->Pos + offset, 0);
            window->Size = ImTrunc(window->Size * scale);
            window->SizeFull = ImTrunc(window->SizeFull * scale);
        }
        return;
    }
    if (g.IO.KeyCtrl)
        return;

    // Mouse wheel scrolling
    // Read about io.MouseWheelRequestAxisSwap and its issue on Mac+Emscripten in UpdateMouseInputs()
    if (g.IO.MouseWheelRequestAxisSwap)
        wheel = ImVec2(wheel.y, 0.0f);

    // Maintain a rough average of moving magnitude on both axises
    // FIXME: should by based on wall clock time rather than frame-counter
    g.WheelingAxisAvg.x = ImExponentialMovingAverage(g.WheelingAxisAvg.x, ImAbs(wheel.x), 30);
    g.WheelingAxisAvg.y = ImExponentialMovingAverage(g.WheelingAxisAvg.y, ImAbs(wheel.y), 30);

    // In the rare situation where FindBestWheelingWindow() had to defer first frame of wheeling due to ambiguous main axis, reinject it now.
    wheel += g.WheelingWindowWheelRemainder;
    g.WheelingWindowWheelRemainder = ImVec2(0.0f, 0.0f);
    if (wheel.x == 0.0f && wheel.y == 0.0f)
        return;

    // Mouse wheel scrolling: find target and apply
    // - don't renew lock if axis doesn't apply on the window.
    // - select a main axis when both axises are being moved.
    if (ImGuiWindow* window = (g.WheelingWindow ? g.WheelingWindow : FindBestWheelingWindow(wheel)))
        if (!(window->Flags & ImGuiWindowFlags_NoScrollWithMouse) && !(window->Flags & ImGuiWindowFlags_NoMouseInputs))
        {
            bool do_scroll[2] = { wheel.x != 0.0f && window->ScrollMax.x != 0.0f, wheel.y != 0.0f && window->ScrollMax.y != 0.0f };
            if (do_scroll[ImGuiAxis_X] && do_scroll[ImGuiAxis_Y])
                do_scroll[(g.WheelingAxisAvg.x > g.WheelingAxisAvg.y) ? ImGuiAxis_Y : ImGuiAxis_X] = false;
            if (do_scroll[ImGuiAxis_X])
            {
                LockWheelingWindow(window, wheel.x);
                float max_step = window->InnerRect.GetWidth() * 0.67f;
                float scroll_step = ImTrunc(ImMin(2 * window->CalcFontSize(), max_step));
                SetScrollX(window, window->Scroll.x - wheel.x * scroll_step);
                g.WheelingWindowScrolledFrame = g.FrameCount;
            }
            if (do_scroll[ImGuiAxis_Y])
            {
                LockWheelingWindow(window, wheel.y);
                float max_step = window->InnerRect.GetHeight() * 0.67f;
                float scroll_step = ImTrunc(ImMin(5 * window->CalcFontSize(), max_step));
                SetScrollY(window, window->Scroll.y - wheel.y * scroll_step);
                g.WheelingWindowScrolledFrame = g.FrameCount;
            }
        }
}

void ImGui::SetNextFrameWantCaptureKeyboard(bool want_capture_keyboard)
{
    ImGuiContext& g = *GImGui;
    g.WantCaptureKeyboardNextFrame = want_capture_keyboard ? 1 : 0;
}

void ImGui::SetNextFrameWantCaptureMouse(bool want_capture_mouse)
{
    ImGuiContext& g = *GImGui;
    g.WantCaptureMouseNextFrame = want_capture_mouse ? 1 : 0;
}

#ifndef IMGUI_DISABLE_DEBUG_TOOLS
static const char* GetInputSourceName(ImGuiInputSource source)
{
    const char* input_source_names[] = { "None", "Mouse", "Keyboard", "Gamepad", "Clipboard" };
    IM_ASSERT(IM_ARRAYSIZE(input_source_names) == ImGuiInputSource_COUNT && source >= 0 && source < ImGuiInputSource_COUNT);
    return input_source_names[source];
}
static const char* GetMouseSourceName(ImGuiMouseSource source)
{
    const char* mouse_source_names[] = { "Mouse", "TouchScreen", "Pen" };
    IM_ASSERT(IM_ARRAYSIZE(mouse_source_names) == ImGuiMouseSource_COUNT && source >= 0 && source < ImGuiMouseSource_COUNT);
    return mouse_source_names[source];
}
static void DebugPrintInputEvent(const char* prefix, const ImGuiInputEvent* e)
{
    ImGuiContext& g = *GImGui;
    if (e->Type == ImGuiInputEventType_MousePos)    { if (e->MousePos.PosX == -FLT_MAX && e->MousePos.PosY == -FLT_MAX) IMGUI_DEBUG_LOG_IO("[io] %s: MousePos (-FLT_MAX, -FLT_MAX)\n", prefix); else IMGUI_DEBUG_LOG_IO("[io] %s: MousePos (%.1f, %.1f) (%s)\n", prefix, e->MousePos.PosX, e->MousePos.PosY, GetMouseSourceName(e->MousePos.MouseSource)); return; }
    if (e->Type == ImGuiInputEventType_MouseButton) { IMGUI_DEBUG_LOG_IO("[io] %s: MouseButton %d %s (%s)\n", prefix, e->MouseButton.Button, e->MouseButton.Down ? "Down" : "Up", GetMouseSourceName(e->MouseButton.MouseSource)); return; }
    if (e->Type == ImGuiInputEventType_MouseWheel)  { IMGUI_DEBUG_LOG_IO("[io] %s: MouseWheel (%.3f, %.3f) (%s)\n", prefix, e->MouseWheel.WheelX, e->MouseWheel.WheelY, GetMouseSourceName(e->MouseWheel.MouseSource)); return; }
    if (e->Type == ImGuiInputEventType_MouseViewport){IMGUI_DEBUG_LOG_IO("[io] %s: MouseViewport (0x%08X)\n", prefix, e->MouseViewport.HoveredViewportID); return; }
    if (e->Type == ImGuiInputEventType_Key)         { IMGUI_DEBUG_LOG_IO("[io] %s: Key \"%s\" %s\n", prefix, ImGui::GetKeyName(e->Key.Key), e->Key.Down ? "Down" : "Up"); return; }
    if (e->Type == ImGuiInputEventType_Text)        { IMGUI_DEBUG_LOG_IO("[io] %s: Text: %c (U+%08X)\n", prefix, e->Text.Char, e->Text.Char); return; }
    if (e->Type == ImGuiInputEventType_Focus)       { IMGUI_DEBUG_LOG_IO("[io] %s: AppFocused %d\n", prefix, e->AppFocused.Focused); return; }
}
#endif

// Process input queue
// We always call this with the value of 'bool g.IO.ConfigInputTrickleEventQueue'.
// - trickle_fast_inputs = false : process all events, turn into flattened input state (e.g. successive down/up/down/up will be lost)
// - trickle_fast_inputs = true  : process as many events as possible (successive down/up/down/up will be trickled over several frames so nothing is lost) (new feature in 1.87)
void ImGui::UpdateInputEvents(bool trickle_fast_inputs)
{
    ImGuiContext& g = *GImGui;
    ImGuiIO& io = g.IO;

    // Only trickle chars<>key when working with InputText()
    // FIXME: InputText() could parse event trail?
    // FIXME: Could specialize chars<>keys trickling rules for control keys (those not typically associated to characters)
    const bool trickle_interleaved_keys_and_text = (trickle_fast_inputs && g.WantTextInputNextFrame == 1);

    bool mouse_moved = false, mouse_wheeled = false, key_changed = false, text_inputted = false;
    int  mouse_button_changed = 0x00;
    ImBitArray<ImGuiKey_KeysData_SIZE> key_changed_mask;

    int event_n = 0;
    for (; event_n < g.InputEventsQueue.Size; event_n++)
    {
        ImGuiInputEvent* e = &g.InputEventsQueue[event_n];
        if (e->Type == ImGuiInputEventType_MousePos)
        {
            if (g.IO.WantSetMousePos)
                continue;
            // Trickling Rule: Stop processing queued events if we already handled a mouse button change
            ImVec2 event_pos(e->MousePos.PosX, e->MousePos.PosY);
            if (trickle_fast_inputs && (mouse_button_changed != 0 || mouse_wheeled || key_changed || text_inputted))
                break;
            io.MousePos = event_pos;
            io.MouseSource = e->MousePos.MouseSource;
            mouse_moved = true;
        }
        else if (e->Type == ImGuiInputEventType_MouseButton)
        {
            // Trickling Rule: Stop processing queued events if we got multiple action on the same button
            const ImGuiMouseButton button = e->MouseButton.Button;
            IM_ASSERT(button >= 0 && button < ImGuiMouseButton_COUNT);
            if (trickle_fast_inputs && ((mouse_button_changed & (1 << button)) || mouse_wheeled))
                break;
            if (trickle_fast_inputs && e->MouseButton.MouseSource == ImGuiMouseSource_TouchScreen && mouse_moved) // #2702: TouchScreen have no initial hover.
                break;
            io.MouseDown[button] = e->MouseButton.Down;
            io.MouseSource = e->MouseButton.MouseSource;
            mouse_button_changed |= (1 << button);
        }
        else if (e->Type == ImGuiInputEventType_MouseWheel)
        {
            // Trickling Rule: Stop processing queued events if we got multiple action on the event
            if (trickle_fast_inputs && (mouse_moved || mouse_button_changed != 0))
                break;
            io.MouseWheelH += e->MouseWheel.WheelX;
            io.MouseWheel += e->MouseWheel.WheelY;
            io.MouseSource = e->MouseWheel.MouseSource;
            mouse_wheeled = true;
        }
        else if (e->Type == ImGuiInputEventType_MouseViewport)
        {
            io.MouseHoveredViewport = e->MouseViewport.HoveredViewportID;
        }
        else if (e->Type == ImGuiInputEventType_Key)
        {
            // Trickling Rule: Stop processing queued events if we got multiple action on the same button
            ImGuiKey key = e->Key.Key;
            IM_ASSERT(key != ImGuiKey_None);
            ImGuiKeyData* key_data = GetKeyData(key);
            const int key_data_index = (int)(key_data - g.IO.KeysData);
            if (trickle_fast_inputs && key_data->Down != e->Key.Down && (key_changed_mask.TestBit(key_data_index) || text_inputted || mouse_button_changed != 0))
                break;
            key_data->Down = e->Key.Down;
            key_data->AnalogValue = e->Key.AnalogValue;
            key_changed = true;
            key_changed_mask.SetBit(key_data_index);

            // Allow legacy code using io.KeysDown[GetKeyIndex()] with new backends
#ifndef IMGUI_DISABLE_OBSOLETE_KEYIO
            io.KeysDown[key_data_index] = key_data->Down;
            if (io.KeyMap[key_data_index] != -1)
                io.KeysDown[io.KeyMap[key_data_index]] = key_data->Down;
#endif
        }
        else if (e->Type == ImGuiInputEventType_Text)
        {
            // Trickling Rule: Stop processing queued events if keys/mouse have been interacted with
            if (trickle_fast_inputs && ((key_changed && trickle_interleaved_keys_and_text) || mouse_button_changed != 0 || mouse_moved || mouse_wheeled))
                break;
            unsigned int c = e->Text.Char;
            io.InputQueueCharacters.push_back(c <= IM_UNICODE_CODEPOINT_MAX ? (ImWchar)c : IM_UNICODE_CODEPOINT_INVALID);
            if (trickle_interleaved_keys_and_text)
                text_inputted = true;
        }
        else if (e->Type == ImGuiInputEventType_Focus)
        {
            // We intentionally overwrite this and process in NewFrame(), in order to give a chance
            // to multi-viewports backends to queue AddFocusEvent(false) + AddFocusEvent(true) in same frame.
            const bool focus_lost = !e->AppFocused.Focused;
            io.AppFocusLost = focus_lost;
        }
        else
        {
            IM_ASSERT(0 && "Unknown event!");
        }
    }

    // Record trail (for domain-specific applications wanting to access a precise trail)
    //if (event_n != 0) IMGUI_DEBUG_LOG_IO("Processed: %d / Remaining: %d\n", event_n, g.InputEventsQueue.Size - event_n);
    for (int n = 0; n < event_n; n++)
        g.InputEventsTrail.push_back(g.InputEventsQueue[n]);

    // [DEBUG]
#ifndef IMGUI_DISABLE_DEBUG_TOOLS
    if (event_n != 0 && (g.DebugLogFlags & ImGuiDebugLogFlags_EventIO))
        for (int n = 0; n < g.InputEventsQueue.Size; n++)
            DebugPrintInputEvent(n < event_n ? "Processed" : "Remaining", &g.InputEventsQueue[n]);
#endif

    // Remaining events will be processed on the next frame
    if (event_n == g.InputEventsQueue.Size)
        g.InputEventsQueue.resize(0);
    else
        g.InputEventsQueue.erase(g.InputEventsQueue.Data, g.InputEventsQueue.Data + event_n);

    // Clear buttons state when focus is lost
    // - this is useful so e.g. releasing Alt after focus loss on Alt-Tab doesn't trigger the Alt menu toggle.
    // - we clear in EndFrame() and not now in order allow application/user code polling this flag
    //   (e.g. custom backend may want to clear additional data, custom widgets may want to react with a "canceling" event).
    if (g.IO.AppFocusLost)
        g.IO.ClearInputKeys();
}

ImGuiID ImGui::GetKeyOwner(ImGuiKey key)
{
    if (!IsNamedKeyOrModKey(key))
        return ImGuiKeyOwner_None;

    ImGuiContext& g = *GImGui;
    ImGuiKeyOwnerData* owner_data = GetKeyOwnerData(&g, key);
    ImGuiID owner_id = owner_data->OwnerCurr;

    if (g.ActiveIdUsingAllKeyboardKeys && owner_id != g.ActiveId && owner_id != ImGuiKeyOwner_Any)
        if (key >= ImGuiKey_Keyboard_BEGIN && key < ImGuiKey_Keyboard_END)
            return ImGuiKeyOwner_None;

    return owner_id;
}

// TestKeyOwner(..., ID)   : (owner == None || owner == ID)
// TestKeyOwner(..., None) : (owner == None)
// TestKeyOwner(..., Any)  : no owner test
// All paths are also testing for key not being locked, for the rare cases that key have been locked with using ImGuiInputFlags_LockXXX flags.
bool ImGui::TestKeyOwner(ImGuiKey key, ImGuiID owner_id)
{
    if (!IsNamedKeyOrModKey(key))
        return true;

    ImGuiContext& g = *GImGui;
    if (g.ActiveIdUsingAllKeyboardKeys && owner_id != g.ActiveId && owner_id != ImGuiKeyOwner_Any)
        if (key >= ImGuiKey_Keyboard_BEGIN && key < ImGuiKey_Keyboard_END)
            return false;

    ImGuiKeyOwnerData* owner_data = GetKeyOwnerData(&g, key);
    if (owner_id == ImGuiKeyOwner_Any)
        return (owner_data->LockThisFrame == false);

    // Note: SetKeyOwner() sets OwnerCurr. It is not strictly required for most mouse routing overlap (because of ActiveId/HoveredId
    // are acting as filter before this has a chance to filter), but sane as soon as user tries to look into things.
    // Setting OwnerCurr in SetKeyOwner() is more consistent than testing OwnerNext here: would be inconsistent with getter and other functions.
    if (owner_data->OwnerCurr != owner_id)
    {
        if (owner_data->LockThisFrame)
            return false;
        if (owner_data->OwnerCurr != ImGuiKeyOwner_None)
            return false;
    }

    return true;
}

// _LockXXX flags are useful to lock keys away from code which is not input-owner aware.
// When using _LockXXX flags, you can use ImGuiKeyOwner_Any to lock keys from everyone.
// - SetKeyOwner(..., None)              : clears owner
// - SetKeyOwner(..., Any, !Lock)        : illegal (assert)
// - SetKeyOwner(..., Any or None, Lock) : set lock
void ImGui::SetKeyOwner(ImGuiKey key, ImGuiID owner_id, ImGuiInputFlags flags)
{
    IM_ASSERT(IsNamedKeyOrModKey(key) && (owner_id != ImGuiKeyOwner_Any || (flags & (ImGuiInputFlags_LockThisFrame | ImGuiInputFlags_LockUntilRelease)))); // Can only use _Any with _LockXXX flags (to eat a key away without an ID to retrieve it)
    IM_ASSERT((flags & ~ImGuiInputFlags_SupportedBySetKeyOwner) == 0); // Passing flags not supported by this function!

    ImGuiContext& g = *GImGui;
    ImGuiKeyOwnerData* owner_data = GetKeyOwnerData(&g, key);
    owner_data->OwnerCurr = owner_data->OwnerNext = owner_id;

    // We cannot lock by default as it would likely break lots of legacy code.
    // In the case of using LockUntilRelease while key is not down we still lock during the frame (no key_data->Down test)
    owner_data->LockUntilRelease = (flags & ImGuiInputFlags_LockUntilRelease) != 0;
    owner_data->LockThisFrame = (flags & ImGuiInputFlags_LockThisFrame) != 0 || (owner_data->LockUntilRelease);
}

// Rarely used helper
void ImGui::SetKeyOwnersForKeyChord(ImGuiKeyChord key_chord, ImGuiID owner_id, ImGuiInputFlags flags)
{
    if (key_chord & ImGuiMod_Ctrl)      { SetKeyOwner(ImGuiMod_Ctrl, owner_id, flags); }
    if (key_chord & ImGuiMod_Shift)     { SetKeyOwner(ImGuiMod_Shift, owner_id, flags); }
    if (key_chord & ImGuiMod_Alt)       { SetKeyOwner(ImGuiMod_Alt, owner_id, flags); }
    if (key_chord & ImGuiMod_Super)     { SetKeyOwner(ImGuiMod_Super, owner_id, flags); }
    if (key_chord & ImGuiMod_Shortcut)  { SetKeyOwner(ImGuiMod_Shortcut, owner_id, flags); }
    if (key_chord & ~ImGuiMod_Mask_)    { SetKeyOwner((ImGuiKey)(key_chord & ~ImGuiMod_Mask_), owner_id, flags); }
}

// This is more or less equivalent to:
//   if (IsItemHovered() || IsItemActive())
//       SetKeyOwner(key, GetItemID());
// Extensive uses of that (e.g. many calls for a single item) may want to manually perform the tests once and then call SetKeyOwner() multiple times.
// More advanced usage scenarios may want to call SetKeyOwner() manually based on different condition.
// Worth noting is that only one item can be hovered and only one item can be active, therefore this usage pattern doesn't need to bother with routing and priority.
void ImGui::SetItemKeyOwner(ImGuiKey key, ImGuiInputFlags flags)
{
    ImGuiContext& g = *GImGui;
    ImGuiID id = g.LastItemData.ID;
    if (id == 0 || (g.HoveredId != id && g.ActiveId != id))
        return;
    if ((flags & ImGuiInputFlags_CondMask_) == 0)
        flags |= ImGuiInputFlags_CondDefault_;
    if ((g.HoveredId == id && (flags & ImGuiInputFlags_CondHovered)) || (g.ActiveId == id && (flags & ImGuiInputFlags_CondActive)))
    {
        IM_ASSERT((flags & ~ImGuiInputFlags_SupportedBySetItemKeyOwner) == 0); // Passing flags not supported by this function!
        SetKeyOwner(key, id, flags & ~ImGuiInputFlags_CondMask_);
    }
}

// This is the only public API until we expose owner_id versions of the API as replacements.
bool ImGui::IsKeyChordPressed(ImGuiKeyChord key_chord)
{
    return IsKeyChordPressed(key_chord, 0, ImGuiInputFlags_None);
}

// This is equivalent to comparing KeyMods + doing a IsKeyPressed()
bool ImGui::IsKeyChordPressed(ImGuiKeyChord key_chord, ImGuiID owner_id, ImGuiInputFlags flags)
{
    ImGuiContext& g = *GImGui;
    if (key_chord & ImGuiMod_Shortcut)
        key_chord = ConvertShortcutMod(key_chord);
    ImGuiKey mods = (ImGuiKey)(key_chord & ImGuiMod_Mask_);
    if (g.IO.KeyMods != mods)
        return false;

    // Special storage location for mods
    ImGuiKey key = (ImGuiKey)(key_chord & ~ImGuiMod_Mask_);
    if (key == ImGuiKey_None)
        key = ConvertSingleModFlagToKey(&g, mods);
    if (!IsKeyPressed(key, owner_id, (flags & (ImGuiInputFlags_Repeat | (ImGuiInputFlags)ImGuiInputFlags_RepeatRateMask_))))
        return false;
    return true;
}

bool ImGui::Shortcut(ImGuiKeyChord key_chord, ImGuiID owner_id, ImGuiInputFlags flags)
{
    // When using (owner_id == 0/Any): SetShortcutRouting() will use CurrentFocusScopeId and filter with this, so IsKeyPressed() is fine with he 0/Any.
    if ((flags & ImGuiInputFlags_RouteMask_) == 0)
        flags |= ImGuiInputFlags_RouteFocused;
    if (!SetShortcutRouting(key_chord, owner_id, flags))
        return false;

    if (!IsKeyChordPressed(key_chord, owner_id, flags))
        return false;
    IM_ASSERT((flags & ~ImGuiInputFlags_SupportedByShortcut) == 0); // Passing flags not supported by this function!
    return true;
}


//-----------------------------------------------------------------------------
// [SECTION] ERROR CHECKING
//-----------------------------------------------------------------------------

// Helper function to verify ABI compatibility between caller code and compiled version of Dear ImGui.
// Verify that the type sizes are matching between the calling file's compilation unit and imgui.cpp's compilation unit
// If this triggers you have an issue:
// - Most commonly: mismatched headers and compiled code version.
// - Or: mismatched configuration #define, compilation settings, packing pragma etc.
//   The configuration settings mentioned in imconfig.h must be set for all compilation units involved with Dear ImGui,
//   which is way it is required you put them in your imconfig file (and not just before including imgui.h).
//   Otherwise it is possible that different compilation units would see different structure layout
bool ImGui::DebugCheckVersionAndDataLayout(const char* version, size_t sz_io, size_t sz_style, size_t sz_vec2, size_t sz_vec4, size_t sz_vert, size_t sz_idx)
{
    bool error = false;
    if (strcmp(version, IMGUI_VERSION) != 0) { error = true; IM_ASSERT(strcmp(version, IMGUI_VERSION) == 0 && "Mismatched version string!"); }
    if (sz_io != sizeof(ImGuiIO)) { error = true; IM_ASSERT(sz_io == sizeof(ImGuiIO) && "Mismatched struct layout!"); }
    if (sz_style != sizeof(ImGuiStyle)) { error = true; IM_ASSERT(sz_style == sizeof(ImGuiStyle) && "Mismatched struct layout!"); }
    if (sz_vec2 != sizeof(ImVec2)) { error = true; IM_ASSERT(sz_vec2 == sizeof(ImVec2) && "Mismatched struct layout!"); }
    if (sz_vec4 != sizeof(ImVec4)) { error = true; IM_ASSERT(sz_vec4 == sizeof(ImVec4) && "Mismatched struct layout!"); }
    if (sz_vert != sizeof(ImDrawVert)) { error = true; IM_ASSERT(sz_vert == sizeof(ImDrawVert) && "Mismatched struct layout!"); }
    if (sz_idx != sizeof(ImDrawIdx)) { error = true; IM_ASSERT(sz_idx == sizeof(ImDrawIdx) && "Mismatched struct layout!"); }
    return !error;
}

// Until 1.89 (IMGUI_VERSION_NUM < 18814) it was legal to use SetCursorPos() to extend the boundary of a parent (e.g. window or table cell)
// This is causing issues and ambiguity and we need to retire that.
// See https://github.com/ocornut/imgui/issues/5548 for more details.
// [Scenario 1]
//  Previously this would make the window content size ~200x200:
//    Begin(...) + SetCursorScreenPos(GetCursorScreenPos() + ImVec2(200,200)) + End();  // NOT OK
//  Instead, please submit an item:
//    Begin(...) + SetCursorScreenPos(GetCursorScreenPos() + ImVec2(200,200)) + Dummy(ImVec2(0,0)) + End(); // OK
//  Alternative:
//    Begin(...) + Dummy(ImVec2(200,200)) + End(); // OK
// [Scenario 2]
//  For reference this is one of the issue what we aim to fix with this change:
//    BeginGroup() + SomeItem("foobar") + SetCursorScreenPos(GetCursorScreenPos()) + EndGroup()
//  The previous logic made SetCursorScreenPos(GetCursorScreenPos()) have a side-effect! It would erroneously incorporate ItemSpacing.y after the item into content size, making the group taller!
//  While this code is a little twisted, no-one would expect SetXXX(GetXXX()) to have a side-effect. Using vertical alignment patterns could trigger this issue.
void ImGui::ErrorCheckUsingSetCursorPosToExtendParentBoundaries()
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    IM_ASSERT(window->DC.IsSetPos);
    window->DC.IsSetPos = false;
#ifdef IMGUI_DISABLE_OBSOLETE_FUNCTIONS
    if (window->DC.CursorPos.x <= window->DC.CursorMaxPos.x && window->DC.CursorPos.y <= window->DC.CursorMaxPos.y)
        return;
    if (window->SkipItems)
        return;
    IM_ASSERT(0 && "Code uses SetCursorPos()/SetCursorScreenPos() to extend window/parent boundaries. Please submit an item e.g. Dummy() to validate extent.");
#else
    window->DC.CursorMaxPos = ImMax(window->DC.CursorMaxPos, window->DC.CursorPos);
#endif
}

static void ImGui::ErrorCheckNewFrameSanityChecks()
{
    ImGuiContext& g = *GImGui;

    // Check user IM_ASSERT macro
    // (IF YOU GET A WARNING OR COMPILE ERROR HERE: it means your assert macro is incorrectly defined!
    //  If your macro uses multiple statements, it NEEDS to be surrounded by a 'do { ... } while (0)' block.
    //  This is a common C/C++ idiom to allow multiple statements macros to be used in control flow blocks.)
    // #define IM_ASSERT(EXPR)   if (SomeCode(EXPR)) SomeMoreCode();                    // Wrong!
    // #define IM_ASSERT(EXPR)   do { if (SomeCode(EXPR)) SomeMoreCode(); } while (0)   // Correct!
    if (true) IM_ASSERT(1); else IM_ASSERT(0);

    // Emscripten backends are often imprecise in their submission of DeltaTime. (#6114, #3644)
    // Ideally the Emscripten app/backend should aim to fix or smooth this value and avoid feeding zero, but we tolerate it.
#ifdef __EMSCRIPTEN__
    if (g.IO.DeltaTime <= 0.0f && g.FrameCount > 0)
        g.IO.DeltaTime = 0.00001f;
#endif

    // Check user data
    // (We pass an error message in the assert expression to make it visible to programmers who are not using a debugger, as most assert handlers display their argument)
    IM_ASSERT(g.Initialized);
    IM_ASSERT((g.IO.DeltaTime > 0.0f || g.FrameCount == 0)              && "Need a positive DeltaTime!");
    IM_ASSERT((g.FrameCount == 0 || g.FrameCountEnded == g.FrameCount)  && "Forgot to call Render() or EndFrame() at the end of the previous frame?");
    IM_ASSERT(g.IO.DisplaySize.x >= 0.0f && g.IO.DisplaySize.y >= 0.0f  && "Invalid DisplaySize value!");
    IM_ASSERT(g.IO.Fonts->IsBuilt()                                     && "Font Atlas not built! Make sure you called ImGui_ImplXXXX_NewFrame() function for renderer backend, which should call io.Fonts->GetTexDataAsRGBA32() / GetTexDataAsAlpha8()");
    IM_ASSERT(g.Style.CurveTessellationTol > 0.0f                       && "Invalid style setting!");
    IM_ASSERT(g.Style.CircleTessellationMaxError > 0.0f                 && "Invalid style setting!");
    IM_ASSERT(g.Style.Alpha >= 0.0f && g.Style.Alpha <= 1.0f            && "Invalid style setting!"); // Allows us to avoid a few clamps in color computations
    IM_ASSERT(g.Style.WindowMinSize.x >= 1.0f && g.Style.WindowMinSize.y >= 1.0f && "Invalid style setting.");
    IM_ASSERT(g.Style.WindowMenuButtonPosition == ImGuiDir_None || g.Style.WindowMenuButtonPosition == ImGuiDir_Left || g.Style.WindowMenuButtonPosition == ImGuiDir_Right);
    IM_ASSERT(g.Style.ColorButtonPosition == ImGuiDir_Left || g.Style.ColorButtonPosition == ImGuiDir_Right);
#ifndef IMGUI_DISABLE_OBSOLETE_KEYIO
    for (int n = ImGuiKey_NamedKey_BEGIN; n < ImGuiKey_COUNT; n++)
        IM_ASSERT(g.IO.KeyMap[n] >= -1 && g.IO.KeyMap[n] < ImGuiKey_LegacyNativeKey_END && "io.KeyMap[] contains an out of bound value (need to be 0..511, or -1 for unmapped key)");

    // Check: required key mapping (we intentionally do NOT check all keys to not pressure user into setting up everything, but Space is required and was only added in 1.60 WIP)
    if ((g.IO.ConfigFlags & ImGuiConfigFlags_NavEnableKeyboard) && g.IO.BackendUsingLegacyKeyArrays == 1)
        IM_ASSERT(g.IO.KeyMap[ImGuiKey_Space] != -1 && "ImGuiKey_Space is not mapped, required for keyboard navigation.");
#endif

    // Check: the io.ConfigWindowsResizeFromEdges option requires backend to honor mouse cursor changes and set the ImGuiBackendFlags_HasMouseCursors flag accordingly.
    if (g.IO.ConfigWindowsResizeFromEdges && !(g.IO.BackendFlags & ImGuiBackendFlags_HasMouseCursors))
        g.IO.ConfigWindowsResizeFromEdges = false;

    // Perform simple check: error if Docking or Viewport are enabled _exactly_ on frame 1 (instead of frame 0 or later), which is a common error leading to loss of .ini data.
    if (g.FrameCount == 1 && (g.IO.ConfigFlags & ImGuiConfigFlags_DockingEnable) && (g.ConfigFlagsLastFrame & ImGuiConfigFlags_DockingEnable) == 0)
        IM_ASSERT(0 && "Please set DockingEnable before the first call to NewFrame()! Otherwise you will lose your .ini settings!");
    if (g.FrameCount == 1 && (g.IO.ConfigFlags & ImGuiConfigFlags_ViewportsEnable) && (g.ConfigFlagsLastFrame & ImGuiConfigFlags_ViewportsEnable) == 0)
        IM_ASSERT(0 && "Please set ViewportsEnable before the first call to NewFrame()! Otherwise you will lose your .ini settings!");

    // Perform simple checks: multi-viewport and platform windows support
    if (g.IO.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
    {
        if ((g.IO.BackendFlags & ImGuiBackendFlags_PlatformHasViewports) && (g.IO.BackendFlags & ImGuiBackendFlags_RendererHasViewports))
        {
            IM_ASSERT((g.FrameCount == 0 || g.FrameCount == g.FrameCountPlatformEnded) && "Forgot to call UpdatePlatformWindows() in main loop after EndFrame()? Check examples/ applications for reference.");
            IM_ASSERT(g.PlatformIO.Platform_CreateWindow  != NULL && "Platform init didn't install handlers?");
            IM_ASSERT(g.PlatformIO.Platform_DestroyWindow != NULL && "Platform init didn't install handlers?");
            IM_ASSERT(g.PlatformIO.Platform_GetWindowPos  != NULL && "Platform init didn't install handlers?");
            IM_ASSERT(g.PlatformIO.Platform_SetWindowPos  != NULL && "Platform init didn't install handlers?");
            IM_ASSERT(g.PlatformIO.Platform_GetWindowSize != NULL && "Platform init didn't install handlers?");
            IM_ASSERT(g.PlatformIO.Platform_SetWindowSize != NULL && "Platform init didn't install handlers?");
            IM_ASSERT(g.PlatformIO.Monitors.Size > 0 && "Platform init didn't setup Monitors list?");
            IM_ASSERT((g.Viewports[0]->PlatformUserData != NULL || g.Viewports[0]->PlatformHandle != NULL) && "Platform init didn't setup main viewport.");
            if (g.IO.ConfigDockingTransparentPayload && (g.IO.ConfigFlags & ImGuiConfigFlags_DockingEnable))
                IM_ASSERT(g.PlatformIO.Platform_SetWindowAlpha != NULL && "Platform_SetWindowAlpha handler is required to use io.ConfigDockingTransparent!");
        }
        else
        {
            // Disable feature, our backends do not support it
            g.IO.ConfigFlags &= ~ImGuiConfigFlags_ViewportsEnable;
        }

        // Perform simple checks on platform monitor data + compute a total bounding box for quick early outs
        for (ImGuiPlatformMonitor& mon : g.PlatformIO.Monitors)
        {
            IM_UNUSED(mon);
            IM_ASSERT(mon.MainSize.x > 0.0f && mon.MainSize.y > 0.0f && "Monitor main bounds not setup properly.");
            IM_ASSERT(ImRect(mon.MainPos, mon.MainPos + mon.MainSize).Contains(ImRect(mon.WorkPos, mon.WorkPos + mon.WorkSize)) && "Monitor work bounds not setup properly. If you don't have work area information, just copy MainPos/MainSize into them.");
            IM_ASSERT(mon.DpiScale != 0.0f);
        }
    }
}

static void ImGui::ErrorCheckEndFrameSanityChecks()
{
    ImGuiContext& g = *GImGui;

    // Verify that io.KeyXXX fields haven't been tampered with. Key mods should not be modified between NewFrame() and EndFrame()
    // One possible reason leading to this assert is that your backends update inputs _AFTER_ NewFrame().
    // It is known that when some modal native windows called mid-frame takes focus away, some backends such as GLFW will
    // send key release events mid-frame. This would normally trigger this assertion and lead to sheared inputs.
    // We silently accommodate for this case by ignoring the case where all io.KeyXXX modifiers were released (aka key_mod_flags == 0),
    // while still correctly asserting on mid-frame key press events.
    const ImGuiKeyChord key_mods = GetMergedModsFromKeys();
    IM_ASSERT((key_mods == 0 || g.IO.KeyMods == key_mods) && "Mismatching io.KeyCtrl/io.KeyShift/io.KeyAlt/io.KeySuper vs io.KeyMods");
    IM_UNUSED(key_mods);

    // [EXPERIMENTAL] Recover from errors: You may call this yourself before EndFrame().
    //ErrorCheckEndFrameRecover();

    // Report when there is a mismatch of Begin/BeginChild vs End/EndChild calls. Important: Remember that the Begin/BeginChild API requires you
    // to always call End/EndChild even if Begin/BeginChild returns false! (this is unfortunately inconsistent with most other Begin* API).
    if (g.CurrentWindowStack.Size != 1)
    {
        if (g.CurrentWindowStack.Size > 1)
        {
            ImGuiWindow* window = g.CurrentWindowStack.back().Window; // <-- This window was not Ended!
            IM_ASSERT_USER_ERROR(g.CurrentWindowStack.Size == 1, "Mismatched Begin/BeginChild vs End/EndChild calls: did you forget to call End/EndChild?");
            IM_UNUSED(window);
            while (g.CurrentWindowStack.Size > 1)
                End();
        }
        else
        {
            IM_ASSERT_USER_ERROR(g.CurrentWindowStack.Size == 1, "Mismatched Begin/BeginChild vs End/EndChild calls: did you call End/EndChild too much?");
        }
    }

    IM_ASSERT_USER_ERROR(g.GroupStack.Size == 0, "Missing EndGroup call!");
}

// Experimental recovery from incorrect usage of BeginXXX/EndXXX/PushXXX/PopXXX calls.
// Must be called during or before EndFrame().
// This is generally flawed as we are not necessarily End/Popping things in the right order.
// FIXME: Can't recover from inside BeginTabItem/EndTabItem yet.
// FIXME: Can't recover from interleaved BeginTabBar/Begin
void    ImGui::ErrorCheckEndFrameRecover(ImGuiErrorLogCallback log_callback, void* user_data)
{
    // PVS-Studio V1044 is "Loop break conditions do not depend on the number of iterations"
    ImGuiContext& g = *GImGui;
    while (g.CurrentWindowStack.Size > 0) //-V1044
    {
        ErrorCheckEndWindowRecover(log_callback, user_data);
        ImGuiWindow* window = g.CurrentWindow;
        if (g.CurrentWindowStack.Size == 1)
        {
            IM_ASSERT(window->IsFallbackWindow);
            break;
        }
        if (window->Flags & ImGuiWindowFlags_ChildWindow)
        {
            if (log_callback) log_callback(user_data, "Recovered from missing EndChild() for '%s'", window->Name);
            EndChild();
        }
        else
        {
            if (log_callback) log_callback(user_data, "Recovered from missing End() for '%s'", window->Name);
            End();
        }
    }
}

// Must be called before End()/EndChild()
void    ImGui::ErrorCheckEndWindowRecover(ImGuiErrorLogCallback log_callback, void* user_data)
{
    ImGuiContext& g = *GImGui;
    while (g.CurrentTable && (g.CurrentTable->OuterWindow == g.CurrentWindow || g.CurrentTable->InnerWindow == g.CurrentWindow))
    {
        if (log_callback) log_callback(user_data, "Recovered from missing EndTable() in '%s'", g.CurrentTable->OuterWindow->Name);
        EndTable();
    }

    ImGuiWindow* window = g.CurrentWindow;
    ImGuiStackSizes* stack_sizes = &g.CurrentWindowStack.back().StackSizesOnBegin;
    IM_ASSERT(window != NULL);
    while (g.CurrentTabBar != NULL) //-V1044
    {
        if (log_callback) log_callback(user_data, "Recovered from missing EndTabBar() in '%s'", window->Name);
        EndTabBar();
    }
    while (window->DC.TreeDepth > 0)
    {
        if (log_callback) log_callback(user_data, "Recovered from missing TreePop() in '%s'", window->Name);
        TreePop();
    }
    while (g.GroupStack.Size > stack_sizes->SizeOfGroupStack) //-V1044
    {
        if (log_callback) log_callback(user_data, "Recovered from missing EndGroup() in '%s'", window->Name);
        EndGroup();
    }
    while (window->IDStack.Size > 1)
    {
        if (log_callback) log_callback(user_data, "Recovered from missing PopID() in '%s'", window->Name);
        PopID();
    }
    while (g.DisabledStackSize > stack_sizes->SizeOfDisabledStack) //-V1044
    {
        if (log_callback) log_callback(user_data, "Recovered from missing EndDisabled() in '%s'", window->Name);
        EndDisabled();
    }
    while (g.ColorStack.Size > stack_sizes->SizeOfColorStack)
    {
        if (log_callback) log_callback(user_data, "Recovered from missing PopStyleColor() in '%s' for ImGuiCol_%s", window->Name, GetStyleColorName(g.ColorStack.back().Col));
        PopStyleColor();
    }
    while (g.ItemFlagsStack.Size > stack_sizes->SizeOfItemFlagsStack) //-V1044
    {
        if (log_callback) log_callback(user_data, "Recovered from missing PopItemFlag() in '%s'", window->Name);
        PopItemFlag();
    }
    while (g.StyleVarStack.Size > stack_sizes->SizeOfStyleVarStack) //-V1044
    {
        if (log_callback) log_callback(user_data, "Recovered from missing PopStyleVar() in '%s'", window->Name);
        PopStyleVar();
    }
    while (g.FontStack.Size > stack_sizes->SizeOfFontStack) //-V1044
    {
        if (log_callback) log_callback(user_data, "Recovered from missing PopFont() in '%s'", window->Name);
        PopFont();
    }
    while (g.FocusScopeStack.Size > stack_sizes->SizeOfFocusScopeStack + 1) //-V1044
    {
        if (log_callback) log_callback(user_data, "Recovered from missing PopFocusScope() in '%s'", window->Name);
        PopFocusScope();
    }
}

// Save current stack sizes for later compare
void ImGuiStackSizes::SetToContextState(ImGuiContext* ctx)
{
    ImGuiContext& g = *ctx;
    ImGuiWindow* window = g.CurrentWindow;
    SizeOfIDStack = (short)window->IDStack.Size;
    SizeOfColorStack = (short)g.ColorStack.Size;
    SizeOfStyleVarStack = (short)g.StyleVarStack.Size;
    SizeOfFontStack = (short)g.FontStack.Size;
    SizeOfFocusScopeStack = (short)g.FocusScopeStack.Size;
    SizeOfGroupStack = (short)g.GroupStack.Size;
    SizeOfItemFlagsStack = (short)g.ItemFlagsStack.Size;
    SizeOfBeginPopupStack = (short)g.BeginPopupStack.Size;
    SizeOfDisabledStack = (short)g.DisabledStackSize;
}

// Compare to detect usage errors
void ImGuiStackSizes::CompareWithContextState(ImGuiContext* ctx)
{
    ImGuiContext& g = *ctx;
    ImGuiWindow* window = g.CurrentWindow;
    IM_UNUSED(window);

    // Window stacks
    // NOT checking: DC.ItemWidth, DC.TextWrapPos (per window) to allow user to conveniently push once and not pop (they are cleared on Begin)
    IM_ASSERT(SizeOfIDStack         == window->IDStack.Size     && "PushID/PopID or TreeNode/TreePop Mismatch!");

    // Global stacks
    // For color, style and font stacks there is an incentive to use Push/Begin/Pop/.../End patterns, so we relax our checks a little to allow them.
    IM_ASSERT(SizeOfGroupStack      == g.GroupStack.Size        && "BeginGroup/EndGroup Mismatch!");
    IM_ASSERT(SizeOfBeginPopupStack == g.BeginPopupStack.Size   && "BeginPopup/EndPopup or BeginMenu/EndMenu Mismatch!");
    IM_ASSERT(SizeOfDisabledStack   == g.DisabledStackSize      && "BeginDisabled/EndDisabled Mismatch!");
    IM_ASSERT(SizeOfItemFlagsStack  >= g.ItemFlagsStack.Size    && "PushItemFlag/PopItemFlag Mismatch!");
    IM_ASSERT(SizeOfColorStack      >= g.ColorStack.Size        && "PushStyleColor/PopStyleColor Mismatch!");
    IM_ASSERT(SizeOfStyleVarStack   >= g.StyleVarStack.Size     && "PushStyleVar/PopStyleVar Mismatch!");
    IM_ASSERT(SizeOfFontStack       >= g.FontStack.Size         && "PushFont/PopFont Mismatch!");
    IM_ASSERT(SizeOfFocusScopeStack == g.FocusScopeStack.Size   && "PushFocusScope/PopFocusScope Mismatch!");
}


//-----------------------------------------------------------------------------
// [SECTION] LAYOUT
//-----------------------------------------------------------------------------
// - ItemSize()
// - ItemAdd()
// - SameLine()
// - GetCursorScreenPos()
// - SetCursorScreenPos()
// - GetCursorPos(), GetCursorPosX(), GetCursorPosY()
// - SetCursorPos(), SetCursorPosX(), SetCursorPosY()
// - GetCursorStartPos()
// - Indent()
// - Unindent()
// - SetNextItemWidth()
// - PushItemWidth()
// - PushMultiItemsWidths()
// - PopItemWidth()
// - CalcItemWidth()
// - CalcItemSize()
// - GetTextLineHeight()
// - GetTextLineHeightWithSpacing()
// - GetFrameHeight()
// - GetFrameHeightWithSpacing()
// - GetContentRegionMax()
// - GetContentRegionMaxAbs() [Internal]
// - GetContentRegionAvail(),
// - GetWindowContentRegionMin(), GetWindowContentRegionMax()
// - BeginGroup()
// - EndGroup()
// Also see in imgui_widgets: tab bars, and in imgui_tables: tables, columns.
//-----------------------------------------------------------------------------

// Advance cursor given item size for layout.
// Register minimum needed size so it can extend the bounding box used for auto-fit calculation.
// See comments in ItemAdd() about how/why the size provided to ItemSize() vs ItemAdd() may often different.
void ImGui::ItemSize(const ImVec2& size, float text_baseline_y)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    if (window->SkipItems)
        return;

    // We increase the height in this function to accommodate for baseline offset.
    // In theory we should be offsetting the starting position (window->DC.CursorPos), that will be the topic of a larger refactor,
    // but since ItemSize() is not yet an API that moves the cursor (to handle e.g. wrapping) enlarging the height has the same effect.
    const float offset_to_match_baseline_y = (text_baseline_y >= 0) ? ImMax(0.0f, window->DC.CurrLineTextBaseOffset - text_baseline_y) : 0.0f;

    const float line_y1 = window->DC.IsSameLine ? window->DC.CursorPosPrevLine.y : window->DC.CursorPos.y;
    const float line_height = ImMax(window->DC.CurrLineSize.y, /*ImMax(*/window->DC.CursorPos.y - line_y1/*, 0.0f)*/ + size.y + offset_to_match_baseline_y);

    // Always align ourselves on pixel boundaries
    //if (g.IO.KeyAlt) window->DrawList->AddRect(window->DC.CursorPos, window->DC.CursorPos + ImVec2(size.x, line_height), IM_COL32(255,0,0,200)); // [DEBUG]
    window->DC.CursorPosPrevLine.x = window->DC.CursorPos.x + size.x;
    window->DC.CursorPosPrevLine.y = line_y1;
    window->DC.CursorPos.x = IM_TRUNC(window->Pos.x + window->DC.Indent.x + window->DC.ColumnsOffset.x);    // Next line
    window->DC.CursorPos.y = IM_TRUNC(line_y1 + line_height + g.Style.ItemSpacing.y);                       // Next line
    window->DC.CursorMaxPos.x = ImMax(window->DC.CursorMaxPos.x, window->DC.CursorPosPrevLine.x);
    window->DC.CursorMaxPos.y = ImMax(window->DC.CursorMaxPos.y, window->DC.CursorPos.y - g.Style.ItemSpacing.y);
    //if (g.IO.KeyAlt) window->DrawList->AddCircle(window->DC.CursorMaxPos, 3.0f, IM_COL32(255,0,0,255), 4); // [DEBUG]

    window->DC.PrevLineSize.y = line_height;
    window->DC.CurrLineSize.y = 0.0f;
    window->DC.PrevLineTextBaseOffset = ImMax(window->DC.CurrLineTextBaseOffset, text_baseline_y);
    window->DC.CurrLineTextBaseOffset = 0.0f;
    window->DC.IsSameLine = window->DC.IsSetPos = false;

    // Horizontal layout mode
    if (window->DC.LayoutType == ImGuiLayoutType_Horizontal)
        SameLine();
}

// Declare item bounding box for clipping and interaction.
// Note that the size can be different than the one provided to ItemSize(). Typically, widgets that spread over available surface
// declare their minimum size requirement to ItemSize() and provide a larger region to ItemAdd() which is used drawing/interaction.
bool ImGui::ItemAdd(const ImRect& bb, ImGuiID id, const ImRect* nav_bb_arg, ImGuiItemFlags extra_flags)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;

    // Set item data
    // (DisplayRect is left untouched, made valid when ImGuiItemStatusFlags_HasDisplayRect is set)
    g.LastItemData.ID = id;
    g.LastItemData.Rect = bb;
    g.LastItemData.NavRect = nav_bb_arg ? *nav_bb_arg : bb;
    g.LastItemData.InFlags = g.CurrentItemFlags | g.NextItemData.ItemFlags | extra_flags;
    g.LastItemData.StatusFlags = ImGuiItemStatusFlags_None;
    // Note: we don't copy 'g.NextItemData.SelectionUserData' to an hypothetical g.LastItemData.SelectionUserData: since the former is not cleared.

    // Directional navigation processing
    if (id != 0)
    {
        KeepAliveID(id);

        // Runs prior to clipping early-out
        //  (a) So that NavInitRequest can be honored, for newly opened windows to select a default widget
        //  (b) So that we can scroll up/down past clipped items. This adds a small O(N) cost to regular navigation requests
        //      unfortunately, but it is still limited to one window. It may not scale very well for windows with ten of
        //      thousands of item, but at least NavMoveRequest is only set on user interaction, aka maximum once a frame.
        //      We could early out with "if (is_clipped && !g.NavInitRequest) return false;" but when we wouldn't be able
        //      to reach unclipped widgets. This would work if user had explicit scrolling control (e.g. mapped on a stick).
        // We intentionally don't check if g.NavWindow != NULL because g.NavAnyRequest should only be set when it is non null.
        // If we crash on a NULL g.NavWindow we need to fix the bug elsewhere.
        if (!(g.LastItemData.InFlags & ImGuiItemFlags_NoNav))
        {
            window->DC.NavLayersActiveMaskNext |= (1 << window->DC.NavLayerCurrent);
            if (g.NavId == id || g.NavAnyRequest)
                if (g.NavWindow->RootWindowForNav == window->RootWindowForNav)
                    if (window == g.NavWindow || ((window->Flags | g.NavWindow->Flags) & ImGuiWindowFlags_NavFlattened))
                        NavProcessItem();
        }

        // [DEBUG] People keep stumbling on this problem and using "" as identifier in the root of a window instead of "##something".
        // Empty identifier are valid and useful in a small amount of cases, but 99.9% of the time you want to use "##something".
        // READ THE FAQ: https://dearimgui.com/faq
        IM_ASSERT(id != window->ID && "Cannot have an empty ID at the root of a window. If you need an empty label, use ## and read the FAQ about how the ID Stack works!");
    }
    g.NextItemData.Flags = ImGuiNextItemDataFlags_None;
    g.NextItemData.ItemFlags = ImGuiItemFlags_None;

#ifdef IMGUI_ENABLE_TEST_ENGINE
    if (id != 0)
        IMGUI_TEST_ENGINE_ITEM_ADD(id, g.LastItemData.NavRect, &g.LastItemData);
#endif

    // Clipping test
    // (FIXME: This is a modified copy of IsClippedEx() so we can reuse the is_rect_visible value)
    //const bool is_clipped = IsClippedEx(bb, id);
    //if (is_clipped)
    //    return false;
    const bool is_rect_visible = bb.Overlaps(window->ClipRect);
    if (!is_rect_visible)
        if (id == 0 || (id != g.ActiveId && id != g.ActiveIdPreviousFrame && id != g.NavId))
            if (!g.LogEnabled)
                return false;

    // [DEBUG]
#ifndef IMGUI_DISABLE_DEBUG_TOOLS
    if (id != 0 && id == g.DebugLocateId)
        DebugLocateItemResolveWithLastItem();
#endif
    //if (g.IO.KeyAlt) window->DrawList->AddRect(bb.Min, bb.Max, IM_COL32(255,255,0,120)); // [DEBUG]
    //if ((g.LastItemData.InFlags & ImGuiItemFlags_NoNav) == 0)
    //    window->DrawList->AddRect(g.LastItemData.NavRect.Min, g.LastItemData.NavRect.Max, IM_COL32(255,255,0,255)); // [DEBUG]

    // We need to calculate this now to take account of the current clipping rectangle (as items like Selectable may change them)
    if (is_rect_visible)
        g.LastItemData.StatusFlags |= ImGuiItemStatusFlags_Visible;
    if (IsMouseHoveringRect(bb.Min, bb.Max))
        g.LastItemData.StatusFlags |= ImGuiItemStatusFlags_HoveredRect;
    return true;
}

// Gets back to previous line and continue with horizontal layout
//      offset_from_start_x == 0 : follow right after previous item
//      offset_from_start_x != 0 : align to specified x position (relative to window/group left)
//      spacing_w < 0            : use default spacing if offset_from_start_x == 0, no spacing if offset_from_start_x != 0
//      spacing_w >= 0           : enforce spacing amount
void ImGui::SameLine(float offset_from_start_x, float spacing_w)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    if (window->SkipItems)
        return;

    if (offset_from_start_x != 0.0f)
    {
        if (spacing_w < 0.0f)
            spacing_w = 0.0f;
        window->DC.CursorPos.x = window->Pos.x - window->Scroll.x + offset_from_start_x + spacing_w + window->DC.GroupOffset.x + window->DC.ColumnsOffset.x;
        window->DC.CursorPos.y = window->DC.CursorPosPrevLine.y;
    }
    else
    {
        if (spacing_w < 0.0f)
            spacing_w = g.Style.ItemSpacing.x;
        window->DC.CursorPos.x = window->DC.CursorPosPrevLine.x + spacing_w;
        window->DC.CursorPos.y = window->DC.CursorPosPrevLine.y;
    }
    window->DC.CurrLineSize = window->DC.PrevLineSize;
    window->DC.CurrLineTextBaseOffset = window->DC.PrevLineTextBaseOffset;
    window->DC.IsSameLine = true;
}

ImVec2 ImGui::GetCursorScreenPos()
{
    ImGuiWindow* window = GetCurrentWindowRead();
    return window->DC.CursorPos;
}

void ImGui::SetCursorScreenPos(const ImVec2& pos)
{
    ImGuiWindow* window = GetCurrentWindow();
    window->DC.CursorPos = pos;
    //window->DC.CursorMaxPos = ImMax(window->DC.CursorMaxPos, window->DC.CursorPos);
    window->DC.IsSetPos = true;
}

// User generally sees positions in window coordinates. Internally we store CursorPos in absolute screen coordinates because it is more convenient.
// Conversion happens as we pass the value to user, but it makes our naming convention confusing because GetCursorPos() == (DC.CursorPos - window.Pos). May want to rename 'DC.CursorPos'.
ImVec2 ImGui::GetCursorPos()
{
    ImGuiWindow* window = GetCurrentWindowRead();
    return window->DC.CursorPos - window->Pos + window->Scroll;
}

float ImGui::GetCursorPosX()
{
    ImGuiWindow* window = GetCurrentWindowRead();
    return window->DC.CursorPos.x - window->Pos.x + window->Scroll.x;
}

float ImGui::GetCursorPosY()
{
    ImGuiWindow* window = GetCurrentWindowRead();
    return window->DC.CursorPos.y - window->Pos.y + window->Scroll.y;
}

void ImGui::SetCursorPos(const ImVec2& local_pos)
{
    ImGuiWindow* window = GetCurrentWindow();
    window->DC.CursorPos = window->Pos - window->Scroll + local_pos;
    //window->DC.CursorMaxPos = ImMax(window->DC.CursorMaxPos, window->DC.CursorPos);
    window->DC.IsSetPos = true;
}

void ImGui::SetCursorPosX(float x)
{
    ImGuiWindow* window = GetCurrentWindow();
    window->DC.CursorPos.x = window->Pos.x - window->Scroll.x + x;
    //window->DC.CursorMaxPos.x = ImMax(window->DC.CursorMaxPos.x, window->DC.CursorPos.x);
    window->DC.IsSetPos = true;
}

void ImGui::SetCursorPosY(float y)
{
    ImGuiWindow* window = GetCurrentWindow();
    window->DC.CursorPos.y = window->Pos.y - window->Scroll.y + y;
    //window->DC.CursorMaxPos.y = ImMax(window->DC.CursorMaxPos.y, window->DC.CursorPos.y);
    window->DC.IsSetPos = true;
}

ImVec2 ImGui::GetCursorStartPos()
{
    ImGuiWindow* window = GetCurrentWindowRead();
    return window->DC.CursorStartPos - window->Pos;
}

void ImGui::Indent(float indent_w)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = GetCurrentWindow();
    window->DC.Indent.x += (indent_w != 0.0f) ? indent_w : g.Style.IndentSpacing;
    window->DC.CursorPos.x = window->Pos.x + window->DC.Indent.x + window->DC.ColumnsOffset.x;
}

void ImGui::Unindent(float indent_w)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = GetCurrentWindow();
    window->DC.Indent.x -= (indent_w != 0.0f) ? indent_w : g.Style.IndentSpacing;
    window->DC.CursorPos.x = window->Pos.x + window->DC.Indent.x + window->DC.ColumnsOffset.x;
}

// Affect large frame+labels widgets only.
void ImGui::SetNextItemWidth(float item_width)
{
    ImGuiContext& g = *GImGui;
    g.NextItemData.Flags |= ImGuiNextItemDataFlags_HasWidth;
    g.NextItemData.Width = item_width;
}

// FIXME: Remove the == 0.0f behavior?
void ImGui::PushItemWidth(float item_width)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    window->DC.ItemWidthStack.push_back(window->DC.ItemWidth); // Backup current width
    window->DC.ItemWidth = (item_width == 0.0f ? window->ItemWidthDefault : item_width);
    g.NextItemData.Flags &= ~ImGuiNextItemDataFlags_HasWidth;
}

void ImGui::PushMultiItemsWidths(int components, float w_full)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    const ImGuiStyle& style = g.Style;
    const float w_item_one  = ImMax(1.0f, IM_TRUNC((w_full - (style.ItemInnerSpacing.x) * (components - 1)) / (float)components));
    const float w_item_last = ImMax(1.0f, IM_TRUNC(w_full - (w_item_one + style.ItemInnerSpacing.x) * (components - 1)));
    window->DC.ItemWidthStack.push_back(window->DC.ItemWidth); // Backup current width
    window->DC.ItemWidthStack.push_back(w_item_last);
    for (int i = 0; i < components - 2; i++)
        window->DC.ItemWidthStack.push_back(w_item_one);
    window->DC.ItemWidth = (components == 1) ? w_item_last : w_item_one;
    g.NextItemData.Flags &= ~ImGuiNextItemDataFlags_HasWidth;
}

void ImGui::PopItemWidth()
{
    ImGuiWindow* window = GetCurrentWindow();
    window->DC.ItemWidth = window->DC.ItemWidthStack.back();
    window->DC.ItemWidthStack.pop_back();
}

// Calculate default item width given value passed to PushItemWidth() or SetNextItemWidth().
// The SetNextItemWidth() data is generally cleared/consumed by ItemAdd() or NextItemData.ClearFlags()
float ImGui::CalcItemWidth()
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    float w;
    if (g.NextItemData.Flags & ImGuiNextItemDataFlags_HasWidth)
        w = g.NextItemData.Width;
    else
        w = window->DC.ItemWidth;
    if (w < 0.0f)
    {
        float region_max_x = GetContentRegionMaxAbs().x;
        w = ImMax(1.0f, region_max_x - window->DC.CursorPos.x + w);
    }
    w = IM_TRUNC(w);
    return w;
}

// [Internal] Calculate full item size given user provided 'size' parameter and default width/height. Default width is often == CalcItemWidth().
// Those two functions CalcItemWidth vs CalcItemSize are awkwardly named because they are not fully symmetrical.
// Note that only CalcItemWidth() is publicly exposed.
// The 4.0f here may be changed to match CalcItemWidth() and/or BeginChild() (right now we have a mismatch which is harmless but undesirable)
ImVec2 ImGui::CalcItemSize(ImVec2 size, float default_w, float default_h)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;

    ImVec2 region_max;
    if (size.x < 0.0f || size.y < 0.0f)
        region_max = GetContentRegionMaxAbs();

    if (size.x == 0.0f)
        size.x = default_w;
    else if (size.x < 0.0f)
        size.x = ImMax(4.0f, region_max.x - window->DC.CursorPos.x + size.x);

    if (size.y == 0.0f)
        size.y = default_h;
    else if (size.y < 0.0f)
        size.y = ImMax(4.0f, region_max.y - window->DC.CursorPos.y + size.y);

    return size;
}

float ImGui::GetTextLineHeight()
{
    ImGuiContext& g = *GImGui;
    return g.FontSize;
}

float ImGui::GetTextLineHeightWithSpacing()
{
    ImGuiContext& g = *GImGui;
    return g.FontSize + g.Style.ItemSpacing.y;
}

float ImGui::GetFrameHeight()
{
    ImGuiContext& g = *GImGui;
    return g.FontSize + g.Style.FramePadding.y * 2.0f;
}

float ImGui::GetFrameHeightWithSpacing()
{
    ImGuiContext& g = *GImGui;
    return g.FontSize + g.Style.FramePadding.y * 2.0f + g.Style.ItemSpacing.y;
}

// FIXME: All the Contents Region function are messy or misleading. WE WILL AIM TO OBSOLETE ALL OF THEM WITH A NEW "WORK RECT" API. Thanks for your patience!

// FIXME: This is in window space (not screen space!).
ImVec2 ImGui::GetContentRegionMax()
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    ImVec2 mx = (window->DC.CurrentColumns || g.CurrentTable) ? window->WorkRect.Max : window->ContentRegionRect.Max;
    return mx - window->Pos;
}

// [Internal] Absolute coordinate. Saner. This is not exposed until we finishing refactoring work rect features.
ImVec2 ImGui::GetContentRegionMaxAbs()
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    ImVec2 mx = (window->DC.CurrentColumns || g.CurrentTable) ? window->WorkRect.Max : window->ContentRegionRect.Max;
    return mx;
}

ImVec2 ImGui::GetContentRegionAvail()
{
    ImGuiWindow* window = GImGui->CurrentWindow;
    return GetContentRegionMaxAbs() - window->DC.CursorPos;
}

// In window space (not screen space!)
ImVec2 ImGui::GetWindowContentRegionMin()
{
    ImGuiWindow* window = GImGui->CurrentWindow;
    return window->ContentRegionRect.Min - window->Pos;
}

ImVec2 ImGui::GetWindowContentRegionMax()
{
    ImGuiWindow* window = GImGui->CurrentWindow;
    return window->ContentRegionRect.Max - window->Pos;
}

// Lock horizontal starting position + capture group bounding box into one "item" (so you can use IsItemHovered() or layout primitives such as SameLine() on whole group, etc.)
// Groups are currently a mishmash of functionalities which should perhaps be clarified and separated.
// FIXME-OPT: Could we safely early out on ->SkipItems?
void ImGui::BeginGroup()
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;

    g.GroupStack.resize(g.GroupStack.Size + 1);
    ImGuiGroupData& group_data = g.GroupStack.back();
    group_data.WindowID = window->ID;
    group_data.BackupCursorPos = window->DC.CursorPos;
    group_data.BackupCursorPosPrevLine = window->DC.CursorPosPrevLine;
    group_data.BackupCursorMaxPos = window->DC.CursorMaxPos;
    group_data.BackupIndent = window->DC.Indent;
    group_data.BackupGroupOffset = window->DC.GroupOffset;
    group_data.BackupCurrLineSize = window->DC.CurrLineSize;
    group_data.BackupCurrLineTextBaseOffset = window->DC.CurrLineTextBaseOffset;
    group_data.BackupActiveIdIsAlive = g.ActiveIdIsAlive;
    group_data.BackupHoveredIdIsAlive = g.HoveredId != 0;
    group_data.BackupIsSameLine = window->DC.IsSameLine;
    group_data.BackupActiveIdPreviousFrameIsAlive = g.ActiveIdPreviousFrameIsAlive;
    group_data.EmitItem = true;

    window->DC.GroupOffset.x = window->DC.CursorPos.x - window->Pos.x - window->DC.ColumnsOffset.x;
    window->DC.Indent = window->DC.GroupOffset;
    window->DC.CursorMaxPos = window->DC.CursorPos;
    window->DC.CurrLineSize = ImVec2(0.0f, 0.0f);
    if (g.LogEnabled)
        g.LogLinePosY = -FLT_MAX; // To enforce a carriage return
}

void ImGui::EndGroup()
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    IM_ASSERT(g.GroupStack.Size > 0); // Mismatched BeginGroup()/EndGroup() calls

    ImGuiGroupData& group_data = g.GroupStack.back();
    IM_ASSERT(group_data.WindowID == window->ID); // EndGroup() in wrong window?

    if (window->DC.IsSetPos)
        ErrorCheckUsingSetCursorPosToExtendParentBoundaries();

    ImRect group_bb(group_data.BackupCursorPos, ImMax(window->DC.CursorMaxPos, group_data.BackupCursorPos));

    window->DC.CursorPos = group_data.BackupCursorPos;
    window->DC.CursorPosPrevLine = group_data.BackupCursorPosPrevLine;
    window->DC.CursorMaxPos = ImMax(group_data.BackupCursorMaxPos, window->DC.CursorMaxPos);
    window->DC.Indent = group_data.BackupIndent;
    window->DC.GroupOffset = group_data.BackupGroupOffset;
    window->DC.CurrLineSize = group_data.BackupCurrLineSize;
    window->DC.CurrLineTextBaseOffset = group_data.BackupCurrLineTextBaseOffset;
    window->DC.IsSameLine = group_data.BackupIsSameLine;
    if (g.LogEnabled)
        g.LogLinePosY = -FLT_MAX; // To enforce a carriage return

    if (!group_data.EmitItem)
    {
        g.GroupStack.pop_back();
        return;
    }

    window->DC.CurrLineTextBaseOffset = ImMax(window->DC.PrevLineTextBaseOffset, group_data.BackupCurrLineTextBaseOffset);      // FIXME: Incorrect, we should grab the base offset from the *first line* of the group but it is hard to obtain now.
    ItemSize(group_bb.GetSize());
    ItemAdd(group_bb, 0, NULL, ImGuiItemFlags_NoTabStop);

    // If the current ActiveId was declared within the boundary of our group, we copy it to LastItemId so IsItemActive(), IsItemDeactivated() etc. will be functional on the entire group.
    // It would be neater if we replaced window.DC.LastItemId by e.g. 'bool LastItemIsActive', but would put a little more burden on individual widgets.
    // Also if you grep for LastItemId you'll notice it is only used in that context.
    // (The two tests not the same because ActiveIdIsAlive is an ID itself, in order to be able to handle ActiveId being overwritten during the frame.)
    const bool group_contains_curr_active_id = (group_data.BackupActiveIdIsAlive != g.ActiveId) && (g.ActiveIdIsAlive == g.ActiveId) && g.ActiveId;
    const bool group_contains_prev_active_id = (group_data.BackupActiveIdPreviousFrameIsAlive == false) && (g.ActiveIdPreviousFrameIsAlive == true);
    if (group_contains_curr_active_id)
        g.LastItemData.ID = g.ActiveId;
    else if (group_contains_prev_active_id)
        g.LastItemData.ID = g.ActiveIdPreviousFrame;
    g.LastItemData.Rect = group_bb;

    // Forward Hovered flag
    const bool group_contains_curr_hovered_id = (group_data.BackupHoveredIdIsAlive == false) && g.HoveredId != 0;
    if (group_contains_curr_hovered_id)
        g.LastItemData.StatusFlags |= ImGuiItemStatusFlags_HoveredWindow;

    // Forward Edited flag
    if (group_contains_curr_active_id && g.ActiveIdHasBeenEditedThisFrame)
        g.LastItemData.StatusFlags |= ImGuiItemStatusFlags_Edited;

    // Forward Deactivated flag
    g.LastItemData.StatusFlags |= ImGuiItemStatusFlags_HasDeactivated;
    if (group_contains_prev_active_id && g.ActiveId != g.ActiveIdPreviousFrame)
        g.LastItemData.StatusFlags |= ImGuiItemStatusFlags_Deactivated;

    g.GroupStack.pop_back();
    if (g.DebugShowGroupRects)
        window->DrawList->AddRect(group_bb.Min, group_bb.Max, IM_COL32(255,0,255,255));   // [Debug]
}


//-----------------------------------------------------------------------------
// [SECTION] SCROLLING
//-----------------------------------------------------------------------------

// Helper to snap on edges when aiming at an item very close to the edge,
// So the difference between WindowPadding and ItemSpacing will be in the visible area after scrolling.
// When we refactor the scrolling API this may be configurable with a flag?
// Note that the effect for this won't be visible on X axis with default Style settings as WindowPadding.x == ItemSpacing.x by default.
static float CalcScrollEdgeSnap(float target, float snap_min, float snap_max, float snap_threshold, float center_ratio)
{
    if (target <= snap_min + snap_threshold)
        return ImLerp(snap_min, target, center_ratio);
    if (target >= snap_max - snap_threshold)
        return ImLerp(target, snap_max, center_ratio);
    return target;
}

static ImVec2 CalcNextScrollFromScrollTargetAndClamp(ImGuiWindow* window)
{
    ImVec2 scroll = window->Scroll;
    ImVec2 decoration_size(window->DecoOuterSizeX1 + window->DecoInnerSizeX1 + window->DecoOuterSizeX2, window->DecoOuterSizeY1 + window->DecoInnerSizeY1 + window->DecoOuterSizeY2);
    for (int axis = 0; axis < 2; axis++)
    {
        if (window->ScrollTarget[axis] < FLT_MAX)
        {
            float center_ratio = window->ScrollTargetCenterRatio[axis];
            float scroll_target = window->ScrollTarget[axis];
            if (window->ScrollTargetEdgeSnapDist[axis] > 0.0f)
            {
                float snap_min = 0.0f;
                float snap_max = window->ScrollMax[axis] + window->SizeFull[axis] - decoration_size[axis];
                scroll_target = CalcScrollEdgeSnap(scroll_target, snap_min, snap_max, window->ScrollTargetEdgeSnapDist[axis], center_ratio);
            }
            scroll[axis] = scroll_target - center_ratio * (window->SizeFull[axis] - decoration_size[axis]);
        }
        scroll[axis] = IM_TRUNC(ImMax(scroll[axis], 0.0f));
        if (!window->Collapsed && !window->SkipItems)
            scroll[axis] = ImMin(scroll[axis], window->ScrollMax[axis]);
    }
    return scroll;
}

void ImGui::ScrollToItem(ImGuiScrollFlags flags)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    ScrollToRectEx(window, g.LastItemData.NavRect, flags);
}

void ImGui::ScrollToRect(ImGuiWindow* window, const ImRect& item_rect, ImGuiScrollFlags flags)
{
    ScrollToRectEx(window, item_rect, flags);
}

// Scroll to keep newly navigated item fully into view
ImVec2 ImGui::ScrollToRectEx(ImGuiWindow* window, const ImRect& item_rect, ImGuiScrollFlags flags)
{
    ImGuiContext& g = *GImGui;
    ImRect scroll_rect(window->InnerRect.Min - ImVec2(1, 1), window->InnerRect.Max + ImVec2(1, 1));
    scroll_rect.Min.x = ImMin(scroll_rect.Min.x + window->DecoInnerSizeX1, scroll_rect.Max.x);
    scroll_rect.Min.y = ImMin(scroll_rect.Min.y + window->DecoInnerSizeY1, scroll_rect.Max.y);
    //GetForegroundDrawList(window)->AddRect(item_rect.Min, item_rect.Max, IM_COL32(255,0,0,255), 0.0f, 0, 5.0f); // [DEBUG]
    //GetForegroundDrawList(window)->AddRect(scroll_rect.Min, scroll_rect.Max, IM_COL32_WHITE); // [DEBUG]

    // Check that only one behavior is selected per axis
    IM_ASSERT((flags & ImGuiScrollFlags_MaskX_) == 0 || ImIsPowerOfTwo(flags & ImGuiScrollFlags_MaskX_));
    IM_ASSERT((flags & ImGuiScrollFlags_MaskY_) == 0 || ImIsPowerOfTwo(flags & ImGuiScrollFlags_MaskY_));

    // Defaults
    ImGuiScrollFlags in_flags = flags;
    if ((flags & ImGuiScrollFlags_MaskX_) == 0 && window->ScrollbarX)
        flags |= ImGuiScrollFlags_KeepVisibleEdgeX;
    if ((flags & ImGuiScrollFlags_MaskY_) == 0)
        flags |= window->Appearing ? ImGuiScrollFlags_AlwaysCenterY : ImGuiScrollFlags_KeepVisibleEdgeY;

    const bool fully_visible_x = item_rect.Min.x >= scroll_rect.Min.x && item_rect.Max.x <= scroll_rect.Max.x;
    const bool fully_visible_y = item_rect.Min.y >= scroll_rect.Min.y && item_rect.Max.y <= scroll_rect.Max.y;
    const bool can_be_fully_visible_x = (item_rect.GetWidth() + g.Style.ItemSpacing.x * 2.0f) <= scroll_rect.GetWidth() || (window->AutoFitFramesX > 0) || (window->Flags & ImGuiWindowFlags_AlwaysAutoResize) != 0;
    const bool can_be_fully_visible_y = (item_rect.GetHeight() + g.Style.ItemSpacing.y * 2.0f) <= scroll_rect.GetHeight() || (window->AutoFitFramesY > 0) || (window->Flags & ImGuiWindowFlags_AlwaysAutoResize) != 0;

    if ((flags & ImGuiScrollFlags_KeepVisibleEdgeX) && !fully_visible_x)
    {
        if (item_rect.Min.x < scroll_rect.Min.x || !can_be_fully_visible_x)
            SetScrollFromPosX(window, item_rect.Min.x - g.Style.ItemSpacing.x - window->Pos.x, 0.0f);
        else if (item_rect.Max.x >= scroll_rect.Max.x)
            SetScrollFromPosX(window, item_rect.Max.x + g.Style.ItemSpacing.x - window->Pos.x, 1.0f);
    }
    else if (((flags & ImGuiScrollFlags_KeepVisibleCenterX) && !fully_visible_x) || (flags & ImGuiScrollFlags_AlwaysCenterX))
    {
        if (can_be_fully_visible_x)
            SetScrollFromPosX(window, ImTrunc((item_rect.Min.x + item_rect.Max.x) * 0.5f) - window->Pos.x, 0.5f);
        else
            SetScrollFromPosX(window, item_rect.Min.x - window->Pos.x, 0.0f);
    }

    if ((flags & ImGuiScrollFlags_KeepVisibleEdgeY) && !fully_visible_y)
    {
        if (item_rect.Min.y < scroll_rect.Min.y || !can_be_fully_visible_y)
            SetScrollFromPosY(window, item_rect.Min.y - g.Style.ItemSpacing.y - window->Pos.y, 0.0f);
        else if (item_rect.Max.y >= scroll_rect.Max.y)
            SetScrollFromPosY(window, item_rect.Max.y + g.Style.ItemSpacing.y - window->Pos.y, 1.0f);
    }
    else if (((flags & ImGuiScrollFlags_KeepVisibleCenterY) && !fully_visible_y) || (flags & ImGuiScrollFlags_AlwaysCenterY))
    {
        if (can_be_fully_visible_y)
            SetScrollFromPosY(window, ImTrunc((item_rect.Min.y + item_rect.Max.y) * 0.5f) - window->Pos.y, 0.5f);
        else
            SetScrollFromPosY(window, item_rect.Min.y - window->Pos.y, 0.0f);
    }

    ImVec2 next_scroll = CalcNextScrollFromScrollTargetAndClamp(window);
    ImVec2 delta_scroll = next_scroll - window->Scroll;

    // Also scroll parent window to keep us into view if necessary
    if (!(flags & ImGuiScrollFlags_NoScrollParent) && (window->Flags & ImGuiWindowFlags_ChildWindow))
    {
        // FIXME-SCROLL: May be an option?
        if ((in_flags & (ImGuiScrollFlags_AlwaysCenterX | ImGuiScrollFlags_KeepVisibleCenterX)) != 0)
            in_flags = (in_flags & ~ImGuiScrollFlags_MaskX_) | ImGuiScrollFlags_KeepVisibleEdgeX;
        if ((in_flags & (ImGuiScrollFlags_AlwaysCenterY | ImGuiScrollFlags_KeepVisibleCenterY)) != 0)
            in_flags = (in_flags & ~ImGuiScrollFlags_MaskY_) | ImGuiScrollFlags_KeepVisibleEdgeY;
        delta_scroll += ScrollToRectEx(window->ParentWindow, ImRect(item_rect.Min - delta_scroll, item_rect.Max - delta_scroll), in_flags);
    }

    return delta_scroll;
}

float ImGui::GetScrollX()
{
    ImGuiWindow* window = GImGui->CurrentWindow;
    return window->Scroll.x;
}

float ImGui::GetScrollY()
{
    ImGuiWindow* window = GImGui->CurrentWindow;
    return window->Scroll.y;
}

float ImGui::GetScrollMaxX()
{
    ImGuiWindow* window = GImGui->CurrentWindow;
    return window->ScrollMax.x;
}

float ImGui::GetScrollMaxY()
{
    ImGuiWindow* window = GImGui->CurrentWindow;
    return window->ScrollMax.y;
}

void ImGui::SetScrollX(ImGuiWindow* window, float scroll_x)
{
    window->ScrollTarget.x = scroll_x;
    window->ScrollTargetCenterRatio.x = 0.0f;
    window->ScrollTargetEdgeSnapDist.x = 0.0f;
}

void ImGui::SetScrollY(ImGuiWindow* window, float scroll_y)
{
    window->ScrollTarget.y = scroll_y;
    window->ScrollTargetCenterRatio.y = 0.0f;
    window->ScrollTargetEdgeSnapDist.y = 0.0f;
}

void ImGui::SetScrollX(float scroll_x)
{
    ImGuiContext& g = *GImGui;
    SetScrollX(g.CurrentWindow, scroll_x);
}

void ImGui::SetScrollY(float scroll_y)
{
    ImGuiContext& g = *GImGui;
    SetScrollY(g.CurrentWindow, scroll_y);
}

// Note that a local position will vary depending on initial scroll value,
// This is a little bit confusing so bear with us:
//  - local_pos = (absolution_pos - window->Pos)
//  - So local_x/local_y are 0.0f for a position at the upper-left corner of a window,
//    and generally local_x/local_y are >(padding+decoration) && <(size-padding-decoration) when in the visible area.
//  - They mostly exist because of legacy API.
// Following the rules above, when trying to work with scrolling code, consider that:
//  - SetScrollFromPosY(0.0f) == SetScrollY(0.0f + scroll.y) == has no effect!
//  - SetScrollFromPosY(-scroll.y) == SetScrollY(-scroll.y + scroll.y) == SetScrollY(0.0f) == reset scroll. Of course writing SetScrollY(0.0f) directly then makes more sense
// We store a target position so centering and clamping can occur on the next frame when we are guaranteed to have a known window size
void ImGui::SetScrollFromPosX(ImGuiWindow* window, float local_x, float center_x_ratio)
{
    IM_ASSERT(center_x_ratio >= 0.0f && center_x_ratio <= 1.0f);
    window->ScrollTarget.x = IM_TRUNC(local_x - window->DecoOuterSizeX1 - window->DecoInnerSizeX1 + window->Scroll.x); // Convert local position to scroll offset
    window->ScrollTargetCenterRatio.x = center_x_ratio;
    window->ScrollTargetEdgeSnapDist.x = 0.0f;
}

void ImGui::SetScrollFromPosY(ImGuiWindow* window, float local_y, float center_y_ratio)
{
    IM_ASSERT(center_y_ratio >= 0.0f && center_y_ratio <= 1.0f);
    window->ScrollTarget.y = IM_TRUNC(local_y - window->DecoOuterSizeY1 - window->DecoInnerSizeY1 + window->Scroll.y); // Convert local position to scroll offset
    window->ScrollTargetCenterRatio.y = center_y_ratio;
    window->ScrollTargetEdgeSnapDist.y = 0.0f;
}

void ImGui::SetScrollFromPosX(float local_x, float center_x_ratio)
{
    ImGuiContext& g = *GImGui;
    SetScrollFromPosX(g.CurrentWindow, local_x, center_x_ratio);
}

void ImGui::SetScrollFromPosY(float local_y, float center_y_ratio)
{
    ImGuiContext& g = *GImGui;
    SetScrollFromPosY(g.CurrentWindow, local_y, center_y_ratio);
}

// center_x_ratio: 0.0f left of last item, 0.5f horizontal center of last item, 1.0f right of last item.
void ImGui::SetScrollHereX(float center_x_ratio)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    float spacing_x = ImMax(window->WindowPadding.x, g.Style.ItemSpacing.x);
    float target_pos_x = ImLerp(g.LastItemData.Rect.Min.x - spacing_x, g.LastItemData.Rect.Max.x + spacing_x, center_x_ratio);
    SetScrollFromPosX(window, target_pos_x - window->Pos.x, center_x_ratio); // Convert from absolute to local pos

    // Tweak: snap on edges when aiming at an item very close to the edge
    window->ScrollTargetEdgeSnapDist.x = ImMax(0.0f, window->WindowPadding.x - spacing_x);
}

// center_y_ratio: 0.0f top of last item, 0.5f vertical center of last item, 1.0f bottom of last item.
void ImGui::SetScrollHereY(float center_y_ratio)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    float spacing_y = ImMax(window->WindowPadding.y, g.Style.ItemSpacing.y);
    float target_pos_y = ImLerp(window->DC.CursorPosPrevLine.y - spacing_y, window->DC.CursorPosPrevLine.y + window->DC.PrevLineSize.y + spacing_y, center_y_ratio);
    SetScrollFromPosY(window, target_pos_y - window->Pos.y, center_y_ratio); // Convert from absolute to local pos

    // Tweak: snap on edges when aiming at an item very close to the edge
    window->ScrollTargetEdgeSnapDist.y = ImMax(0.0f, window->WindowPadding.y - spacing_y);
}

//-----------------------------------------------------------------------------
// [SECTION] TOOLTIPS
//-----------------------------------------------------------------------------

bool ImGui::BeginTooltip()
{
    return BeginTooltipEx(ImGuiTooltipFlags_None, ImGuiWindowFlags_None);
}

bool ImGui::BeginItemTooltip()
{
    if (!IsItemHovered(ImGuiHoveredFlags_ForTooltip))
        return false;
    return BeginTooltipEx(ImGuiTooltipFlags_None, ImGuiWindowFlags_None);
}

bool ImGui::BeginTooltipEx(ImGuiTooltipFlags tooltip_flags, ImGuiWindowFlags extra_window_flags)
{
    ImGuiContext& g = *GImGui;

    if (g.DragDropWithinSource || g.DragDropWithinTarget)
    {
        // Drag and Drop tooltips are positioning differently than other tooltips:
        // - offset visibility to increase visibility around mouse.
        // - never clamp within outer viewport boundary.
        // We call SetNextWindowPos() to enforce position and disable clamping.
        // See FindBestWindowPosForPopup() for positionning logic of other tooltips (not drag and drop ones).
        //ImVec2 tooltip_pos = g.IO.MousePos - g.ActiveIdClickOffset - g.Style.WindowPadding;
        ImVec2 tooltip_pos = g.IO.MousePos + TOOLTIP_DEFAULT_OFFSET * g.Style.MouseCursorScale;
        SetNextWindowPos(tooltip_pos);
        SetNextWindowBgAlpha(g.Style.Colors[ImGuiCol_PopupBg].w * 0.60f);
        //PushStyleVar(ImGuiStyleVar_Alpha, g.Style.Alpha * 0.60f); // This would be nice but e.g ColorButton with checkboard has issue with transparent colors :(
        tooltip_flags |= ImGuiTooltipFlags_OverridePrevious;
    }

    char window_name[16];
    ImFormatString(window_name, IM_ARRAYSIZE(window_name), "##Tooltip_%02d", g.TooltipOverrideCount);
    if (tooltip_flags & ImGuiTooltipFlags_OverridePrevious)
        if (ImGuiWindow* window = FindWindowByName(window_name))
            if (window->Active)
            {
                // Hide previous tooltip from being displayed. We can't easily "reset" the content of a window so we create a new one.
                SetWindowHiddendAndSkipItemsForCurrentFrame(window);
                ImFormatString(window_name, IM_ARRAYSIZE(window_name), "##Tooltip_%02d", ++g.TooltipOverrideCount);
            }
    ImGuiWindowFlags flags = ImGuiWindowFlags_Tooltip | ImGuiWindowFlags_NoInputs | ImGuiWindowFlags_NoTitleBar | ImGuiWindowFlags_NoMove | ImGuiWindowFlags_NoResize | ImGuiWindowFlags_NoSavedSettings | ImGuiWindowFlags_AlwaysAutoResize | ImGuiWindowFlags_NoDocking;
    Begin(window_name, NULL, flags | extra_window_flags);
    // 2023-03-09: Added bool return value to the API, but currently always returning true.
    // If this ever returns false we need to update BeginDragDropSource() accordingly.
    //if (!ret)
    //    End();
    //return ret;
    return true;
}

void ImGui::EndTooltip()
{
    IM_ASSERT(GetCurrentWindowRead()->Flags & ImGuiWindowFlags_Tooltip);   // Mismatched BeginTooltip()/EndTooltip() calls
    End();
}

void ImGui::SetTooltip(const char* fmt, ...)
{
    va_list args;
    va_start(args, fmt);
    SetTooltipV(fmt, args);
    va_end(args);
}

void ImGui::SetTooltipV(const char* fmt, va_list args)
{
    if (!BeginTooltipEx(ImGuiTooltipFlags_OverridePrevious, ImGuiWindowFlags_None))
        return;
    TextV(fmt, args);
    EndTooltip();
}

// Shortcut to use 'style.HoverFlagsForTooltipMouse' or 'style.HoverFlagsForTooltipNav'.
// Defaults to == ImGuiHoveredFlags_Stationary | ImGuiHoveredFlags_DelayShort when using the mouse.
void ImGui::SetItemTooltip(const char* fmt, ...)
{
    va_list args;
    va_start(args, fmt);
    if (IsItemHovered(ImGuiHoveredFlags_ForTooltip))
        SetTooltipV(fmt, args);
    va_end(args);
}

void ImGui::SetItemTooltipV(const char* fmt, va_list args)
{
    if (IsItemHovered(ImGuiHoveredFlags_ForTooltip))
        SetTooltipV(fmt, args);
}


//-----------------------------------------------------------------------------
// [SECTION] POPUPS
//-----------------------------------------------------------------------------

// Supported flags: ImGuiPopupFlags_AnyPopupId, ImGuiPopupFlags_AnyPopupLevel
bool ImGui::IsPopupOpen(ImGuiID id, ImGuiPopupFlags popup_flags)
{
    ImGuiContext& g = *GImGui;
    if (popup_flags & ImGuiPopupFlags_AnyPopupId)
    {
        // Return true if any popup is open at the current BeginPopup() level of the popup stack
        // This may be used to e.g. test for another popups already opened to handle popups priorities at the same level.
        IM_ASSERT(id == 0);
        if (popup_flags & ImGuiPopupFlags_AnyPopupLevel)
            return g.OpenPopupStack.Size > 0;
        else
            return g.OpenPopupStack.Size > g.BeginPopupStack.Size;
    }
    else
    {
        if (popup_flags & ImGuiPopupFlags_AnyPopupLevel)
        {
            // Return true if the popup is open anywhere in the popup stack
            for (ImGuiPopupData& popup_data : g.OpenPopupStack)
                if (popup_data.PopupId == id)
                    return true;
            return false;
        }
        else
        {
            // Return true if the popup is open at the current BeginPopup() level of the popup stack (this is the most-common query)
            return g.OpenPopupStack.Size > g.BeginPopupStack.Size && g.OpenPopupStack[g.BeginPopupStack.Size].PopupId == id;
        }
    }
}

bool ImGui::IsPopupOpen(const char* str_id, ImGuiPopupFlags popup_flags)
{
    ImGuiContext& g = *GImGui;
    ImGuiID id = (popup_flags & ImGuiPopupFlags_AnyPopupId) ? 0 : g.CurrentWindow->GetID(str_id);
    if ((popup_flags & ImGuiPopupFlags_AnyPopupLevel) && id != 0)
        IM_ASSERT(0 && "Cannot use IsPopupOpen() with a string id and ImGuiPopupFlags_AnyPopupLevel."); // But non-string version is legal and used internally
    return IsPopupOpen(id, popup_flags);
}

// Also see FindBlockingModal(NULL)
ImGuiWindow* ImGui::GetTopMostPopupModal()
{
    ImGuiContext& g = *GImGui;
    for (int n = g.OpenPopupStack.Size - 1; n >= 0; n--)
        if (ImGuiWindow* popup = g.OpenPopupStack.Data[n].Window)
            if (popup->Flags & ImGuiWindowFlags_Modal)
                return popup;
    return NULL;
}

// See Demo->Stacked Modal to confirm what this is for.
ImGuiWindow* ImGui::GetTopMostAndVisiblePopupModal()
{
    ImGuiContext& g = *GImGui;
    for (int n = g.OpenPopupStack.Size - 1; n >= 0; n--)
        if (ImGuiWindow* popup = g.OpenPopupStack.Data[n].Window)
            if ((popup->Flags & ImGuiWindowFlags_Modal) && IsWindowActiveAndVisible(popup))
                return popup;
    return NULL;
}

void ImGui::OpenPopup(const char* str_id, ImGuiPopupFlags popup_flags)
{
    ImGuiContext& g = *GImGui;
    ImGuiID id = g.CurrentWindow->GetID(str_id);
    IMGUI_DEBUG_LOG_POPUP("[popup] OpenPopup(\"%s\" -> 0x%08X)\n", str_id, id);
    OpenPopupEx(id, popup_flags);
}

void ImGui::OpenPopup(ImGuiID id, ImGuiPopupFlags popup_flags)
{
    OpenPopupEx(id, popup_flags);
}

// Mark popup as open (toggle toward open state).
// Popups are closed when user click outside, or activate a pressable item, or CloseCurrentPopup() is called within a BeginPopup()/EndPopup() block.
// Popup identifiers are relative to the current ID-stack (so OpenPopup and BeginPopup needs to be at the same level).
// One open popup per level of the popup hierarchy (NB: when assigning we reset the Window member of ImGuiPopupRef to NULL)
void ImGui::OpenPopupEx(ImGuiID id, ImGuiPopupFlags popup_flags)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* parent_window = g.CurrentWindow;
    const int current_stack_size = g.BeginPopupStack.Size;

    if (popup_flags & ImGuiPopupFlags_NoOpenOverExistingPopup)
        if (IsPopupOpen((ImGuiID)0, ImGuiPopupFlags_AnyPopupId))
            return;

    ImGuiPopupData popup_ref; // Tagged as new ref as Window will be set back to NULL if we write this into OpenPopupStack.
    popup_ref.PopupId = id;
    popup_ref.Window = NULL;
    popup_ref.BackupNavWindow = g.NavWindow;            // When popup closes focus may be restored to NavWindow (depend on window type).
    popup_ref.OpenFrameCount = g.FrameCount;
    popup_ref.OpenParentId = parent_window->IDStack.back();
    popup_ref.OpenPopupPos = NavCalcPreferredRefPos();
    popup_ref.OpenMousePos = IsMousePosValid(&g.IO.MousePos) ? g.IO.MousePos : popup_ref.OpenPopupPos;

    IMGUI_DEBUG_LOG_POPUP("[popup] OpenPopupEx(0x%08X)\n", id);
    if (g.OpenPopupStack.Size < current_stack_size + 1)
    {
        g.OpenPopupStack.push_back(popup_ref);
    }
    else
    {
        // Gently handle the user mistakenly calling OpenPopup() every frame. It is a programming mistake! However, if we were to run the regular code path, the ui
        // would become completely unusable because the popup will always be in hidden-while-calculating-size state _while_ claiming focus. Which would be a very confusing
        // situation for the programmer. Instead, we silently allow the popup to proceed, it will keep reappearing and the programming error will be more obvious to understand.
        if (g.OpenPopupStack[current_stack_size].PopupId == id && g.OpenPopupStack[current_stack_size].OpenFrameCount == g.FrameCount - 1)
        {
            g.OpenPopupStack[current_stack_size].OpenFrameCount = popup_ref.OpenFrameCount;
        }
        else
        {
            // Close child popups if any, then flag popup for open/reopen
            ClosePopupToLevel(current_stack_size, false);
            g.OpenPopupStack.push_back(popup_ref);
        }

        // When reopening a popup we first refocus its parent, otherwise if its parent is itself a popup it would get closed by ClosePopupsOverWindow().
        // This is equivalent to what ClosePopupToLevel() does.
        //if (g.OpenPopupStack[current_stack_size].PopupId == id)
        //    FocusWindow(parent_window);
    }
}

// When popups are stacked, clicking on a lower level popups puts focus back to it and close popups above it.
// This function closes any popups that are over 'ref_window'.
void ImGui::ClosePopupsOverWindow(ImGuiWindow* ref_window, bool restore_focus_to_window_under_popup)
{
    ImGuiContext& g = *GImGui;
    if (g.OpenPopupStack.Size == 0)
        return;

    // Don't close our own child popup windows.
    int popup_count_to_keep = 0;
    if (ref_window)
    {
        // Find the highest popup which is a descendant of the reference window (generally reference window = NavWindow)
        for (; popup_count_to_keep < g.OpenPopupStack.Size; popup_count_to_keep++)
        {
            ImGuiPopupData& popup = g.OpenPopupStack[popup_count_to_keep];
            if (!popup.Window)
                continue;
            IM_ASSERT((popup.Window->Flags & ImGuiWindowFlags_Popup) != 0);
            if (popup.Window->Flags & ImGuiWindowFlags_ChildWindow)
                continue;

            // Trim the stack unless the popup is a direct parent of the reference window (the reference window is often the NavWindow)
            // - With this stack of window, clicking/focusing Popup1 will close Popup2 and Popup3:
            //     Window -> Popup1 -> Popup2 -> Popup3
            // - Each popups may contain child windows, which is why we compare ->RootWindowDockTree!
            //     Window -> Popup1 -> Popup1_Child -> Popup2 -> Popup2_Child
            bool ref_window_is_descendent_of_popup = false;
            for (int n = popup_count_to_keep; n < g.OpenPopupStack.Size; n++)
                if (ImGuiWindow* popup_window = g.OpenPopupStack[n].Window)
                    //if (popup_window->RootWindowDockTree == ref_window->RootWindowDockTree) // FIXME-MERGE
                    if (IsWindowWithinBeginStackOf(ref_window, popup_window))
                    {
                        ref_window_is_descendent_of_popup = true;
                        break;
                    }
            if (!ref_window_is_descendent_of_popup)
                break;
        }
    }
    if (popup_count_to_keep < g.OpenPopupStack.Size) // This test is not required but it allows to set a convenient breakpoint on the statement below
    {
        IMGUI_DEBUG_LOG_POPUP("[popup] ClosePopupsOverWindow(\"%s\")\n", ref_window ? ref_window->Name : "<NULL>");
        ClosePopupToLevel(popup_count_to_keep, restore_focus_to_window_under_popup);
    }
}

void ImGui::ClosePopupsExceptModals()
{
    ImGuiContext& g = *GImGui;

    int popup_count_to_keep;
    for (popup_count_to_keep = g.OpenPopupStack.Size; popup_count_to_keep > 0; popup_count_to_keep--)
    {
        ImGuiWindow* window = g.OpenPopupStack[popup_count_to_keep - 1].Window;
        if (!window || (window->Flags & ImGuiWindowFlags_Modal))
            break;
    }
    if (popup_count_to_keep < g.OpenPopupStack.Size) // This test is not required but it allows to set a convenient breakpoint on the statement below
        ClosePopupToLevel(popup_count_to_keep, true);
}

void ImGui::ClosePopupToLevel(int remaining, bool restore_focus_to_window_under_popup)
{
    ImGuiContext& g = *GImGui;
    IMGUI_DEBUG_LOG_POPUP("[popup] ClosePopupToLevel(%d), restore_focus_to_window_under_popup=%d\n", remaining, restore_focus_to_window_under_popup);
    IM_ASSERT(remaining >= 0 && remaining < g.OpenPopupStack.Size);

    // Trim open popup stack
    ImGuiWindow* popup_window = g.OpenPopupStack[remaining].Window;
    ImGuiWindow* popup_backup_nav_window = g.OpenPopupStack[remaining].BackupNavWindow;
    g.OpenPopupStack.resize(remaining);

    if (restore_focus_to_window_under_popup)
    {
        ImGuiWindow* focus_window = (popup_window && popup_window->Flags & ImGuiWindowFlags_ChildMenu) ? popup_window->ParentWindow : popup_backup_nav_window;
        if (focus_window && !focus_window->WasActive && popup_window)
            FocusTopMostWindowUnderOne(popup_window, NULL, NULL, ImGuiFocusRequestFlags_RestoreFocusedChild); // Fallback
        else
            FocusWindow(focus_window, (g.NavLayer == ImGuiNavLayer_Main) ? ImGuiFocusRequestFlags_RestoreFocusedChild : ImGuiFocusRequestFlags_None);
    }
}

// Close the popup we have begin-ed into.
void ImGui::CloseCurrentPopup()
{
    ImGuiContext& g = *GImGui;
    int popup_idx = g.BeginPopupStack.Size - 1;
    if (popup_idx < 0 || popup_idx >= g.OpenPopupStack.Size || g.BeginPopupStack[popup_idx].PopupId != g.OpenPopupStack[popup_idx].PopupId)
        return;

    // Closing a menu closes its top-most parent popup (unless a modal)
    while (popup_idx > 0)
    {
        ImGuiWindow* popup_window = g.OpenPopupStack[popup_idx].Window;
        ImGuiWindow* parent_popup_window = g.OpenPopupStack[popup_idx - 1].Window;
        bool close_parent = false;
        if (popup_window && (popup_window->Flags & ImGuiWindowFlags_ChildMenu))
            if (parent_popup_window && !(parent_popup_window->Flags & ImGuiWindowFlags_MenuBar))
                close_parent = true;
        if (!close_parent)
            break;
        popup_idx--;
    }
    IMGUI_DEBUG_LOG_POPUP("[popup] CloseCurrentPopup %d -> %d\n", g.BeginPopupStack.Size - 1, popup_idx);
    ClosePopupToLevel(popup_idx, true);

    // A common pattern is to close a popup when selecting a menu item/selectable that will open another window.
    // To improve this usage pattern, we avoid nav highlight for a single frame in the parent window.
    // Similarly, we could avoid mouse hover highlight in this window but it is less visually problematic.
    if (ImGuiWindow* window = g.NavWindow)
        window->DC.NavHideHighlightOneFrame = true;
}

// Attention! BeginPopup() adds default flags which BeginPopupEx()!
bool ImGui::BeginPopupEx(ImGuiID id, ImGuiWindowFlags flags)
{
    ImGuiContext& g = *GImGui;
    if (!IsPopupOpen(id, ImGuiPopupFlags_None))
    {
        g.NextWindowData.ClearFlags(); // We behave like Begin() and need to consume those values
        return false;
    }

    char name[20];
    if (flags & ImGuiWindowFlags_ChildMenu)
        ImFormatString(name, IM_ARRAYSIZE(name), "##Menu_%02d", g.BeginMenuCount); // Recycle windows based on depth
    else
        ImFormatString(name, IM_ARRAYSIZE(name), "##Popup_%08x", id); // Not recycling, so we can close/open during the same frame

    flags |= ImGuiWindowFlags_Popup | ImGuiWindowFlags_NoDocking;
    bool is_open = Begin(name, NULL, flags);
    if (!is_open) // NB: Begin can return false when the popup is completely clipped (e.g. zero size display)
        EndPopup();

    return is_open;
}

bool ImGui::BeginPopup(const char* str_id, ImGuiWindowFlags flags)
{
    ImGuiContext& g = *GImGui;
    if (g.OpenPopupStack.Size <= g.BeginPopupStack.Size) // Early out for performance
    {
        g.NextWindowData.ClearFlags(); // We behave like Begin() and need to consume those values
        return false;
    }
    flags |= ImGuiWindowFlags_AlwaysAutoResize | ImGuiWindowFlags_NoTitleBar | ImGuiWindowFlags_NoSavedSettings;
    ImGuiID id = g.CurrentWindow->GetID(str_id);
    return BeginPopupEx(id, flags);
}

// If 'p_open' is specified for a modal popup window, the popup will have a regular close button which will close the popup.
// Note that popup visibility status is owned by Dear ImGui (and manipulated with e.g. OpenPopup).
// - *p_open set back to false in BeginPopupModal() when popup is not open.
// - if you set *p_open to false before calling BeginPopupModal(), it will close the popup.
bool ImGui::BeginPopupModal(const char* name, bool* p_open, ImGuiWindowFlags flags)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    const ImGuiID id = window->GetID(name);
    if (!IsPopupOpen(id, ImGuiPopupFlags_None))
    {
        g.NextWindowData.ClearFlags(); // We behave like Begin() and need to consume those values
        if (p_open && *p_open)
            *p_open = false;
        return false;
    }

    // Center modal windows by default for increased visibility
    // (this won't really last as settings will kick in, and is mostly for backward compatibility. user may do the same themselves)
    // FIXME: Should test for (PosCond & window->SetWindowPosAllowFlags) with the upcoming window.
    if ((g.NextWindowData.Flags & ImGuiNextWindowDataFlags_HasPos) == 0)
    {
        const ImGuiViewport* viewport = window->WasActive ? window->Viewport : GetMainViewport(); // FIXME-VIEWPORT: What may be our reference viewport?
        SetNextWindowPos(viewport->GetCenter(), ImGuiCond_FirstUseEver, ImVec2(0.5f, 0.5f));
    }

    flags |= ImGuiWindowFlags_Popup | ImGuiWindowFlags_Modal | ImGuiWindowFlags_NoCollapse | ImGuiWindowFlags_NoDocking;
    const bool is_open = Begin(name, p_open, flags);
    if (!is_open || (p_open && !*p_open)) // NB: is_open can be 'false' when the popup is completely clipped (e.g. zero size display)
    {
        EndPopup();
        if (is_open)
            ClosePopupToLevel(g.BeginPopupStack.Size, true);
        return false;
    }
    return is_open;
}

void ImGui::EndPopup()
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    IM_ASSERT(window->Flags & ImGuiWindowFlags_Popup);  // Mismatched BeginPopup()/EndPopup() calls
    IM_ASSERT(g.BeginPopupStack.Size > 0);

    // Make all menus and popups wrap around for now, may need to expose that policy (e.g. focus scope could include wrap/loop policy flags used by new move requests)
    if (g.NavWindow == window)
        NavMoveRequestTryWrapping(window, ImGuiNavMoveFlags_LoopY);

    // Child-popups don't need to be laid out
    IM_ASSERT(g.WithinEndChild == false);
    if (window->Flags & ImGuiWindowFlags_ChildWindow)
        g.WithinEndChild = true;
    End();
    g.WithinEndChild = false;
}

// Helper to open a popup if mouse button is released over the item
// - This is essentially the same as BeginPopupContextItem() but without the trailing BeginPopup()
void ImGui::OpenPopupOnItemClick(const char* str_id, ImGuiPopupFlags popup_flags)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    int mouse_button = (popup_flags & ImGuiPopupFlags_MouseButtonMask_);
    if (IsMouseReleased(mouse_button) && IsItemHovered(ImGuiHoveredFlags_AllowWhenBlockedByPopup))
    {
        ImGuiID id = str_id ? window->GetID(str_id) : g.LastItemData.ID;    // If user hasn't passed an ID, we can use the LastItemID. Using LastItemID as a Popup ID won't conflict!
        IM_ASSERT(id != 0);                                             // You cannot pass a NULL str_id if the last item has no identifier (e.g. a Text() item)
        OpenPopupEx(id, popup_flags);
    }
}

// This is a helper to handle the simplest case of associating one named popup to one given widget.
// - To create a popup associated to the last item, you generally want to pass a NULL value to str_id.
// - To create a popup with a specific identifier, pass it in str_id.
//    - This is useful when using using BeginPopupContextItem() on an item which doesn't have an identifier, e.g. a Text() call.
//    - This is useful when multiple code locations may want to manipulate/open the same popup, given an explicit id.
// - You may want to handle the whole on user side if you have specific needs (e.g. tweaking IsItemHovered() parameters).
//   This is essentially the same as:
//       id = str_id ? GetID(str_id) : GetItemID();
//       OpenPopupOnItemClick(str_id, ImGuiPopupFlags_MouseButtonRight);
//       return BeginPopup(id);
//   Which is essentially the same as:
//       id = str_id ? GetID(str_id) : GetItemID();
//       if (IsItemHovered() && IsMouseReleased(ImGuiMouseButton_Right))
//           OpenPopup(id);
//       return BeginPopup(id);
//   The main difference being that this is tweaked to avoid computing the ID twice.
bool ImGui::BeginPopupContextItem(const char* str_id, ImGuiPopupFlags popup_flags)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    if (window->SkipItems)
        return false;
    ImGuiID id = str_id ? window->GetID(str_id) : g.LastItemData.ID;    // If user hasn't passed an ID, we can use the LastItemID. Using LastItemID as a Popup ID won't conflict!
    IM_ASSERT(id != 0);                                             // You cannot pass a NULL str_id if the last item has no identifier (e.g. a Text() item)
    int mouse_button = (popup_flags & ImGuiPopupFlags_MouseButtonMask_);
    if (IsMouseReleased(mouse_button) && IsItemHovered(ImGuiHoveredFlags_AllowWhenBlockedByPopup))
        OpenPopupEx(id, popup_flags);
    return BeginPopupEx(id, ImGuiWindowFlags_AlwaysAutoResize | ImGuiWindowFlags_NoTitleBar | ImGuiWindowFlags_NoSavedSettings);
}

bool ImGui::BeginPopupContextWindow(const char* str_id, ImGuiPopupFlags popup_flags)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    if (!str_id)
        str_id = "window_context";
    ImGuiID id = window->GetID(str_id);
    int mouse_button = (popup_flags & ImGuiPopupFlags_MouseButtonMask_);
    if (IsMouseReleased(mouse_button) && IsWindowHovered(ImGuiHoveredFlags_AllowWhenBlockedByPopup))
        if (!(popup_flags & ImGuiPopupFlags_NoOpenOverItems) || !IsAnyItemHovered())
            OpenPopupEx(id, popup_flags);
    return BeginPopupEx(id, ImGuiWindowFlags_AlwaysAutoResize | ImGuiWindowFlags_NoTitleBar | ImGuiWindowFlags_NoSavedSettings);
}

bool ImGui::BeginPopupContextVoid(const char* str_id, ImGuiPopupFlags popup_flags)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    if (!str_id)
        str_id = "void_context";
    ImGuiID id = window->GetID(str_id);
    int mouse_button = (popup_flags & ImGuiPopupFlags_MouseButtonMask_);
    if (IsMouseReleased(mouse_button) && !IsWindowHovered(ImGuiHoveredFlags_AnyWindow))
        if (GetTopMostPopupModal() == NULL)
            OpenPopupEx(id, popup_flags);
    return BeginPopupEx(id, ImGuiWindowFlags_AlwaysAutoResize | ImGuiWindowFlags_NoTitleBar | ImGuiWindowFlags_NoSavedSettings);
}

// r_avoid = the rectangle to avoid (e.g. for tooltip it is a rectangle around the mouse cursor which we want to avoid. for popups it's a small point around the cursor.)
// r_outer = the visible area rectangle, minus safe area padding. If our popup size won't fit because of safe area padding we ignore it.
// (r_outer is usually equivalent to the viewport rectangle minus padding, but when multi-viewports are enabled and monitor
//  information are available, it may represent the entire platform monitor from the frame of reference of the current viewport.
//  this allows us to have tooltips/popups displayed out of the parent viewport.)
ImVec2 ImGui::FindBestWindowPosForPopupEx(const ImVec2& ref_pos, const ImVec2& size, ImGuiDir* last_dir, const ImRect& r_outer, const ImRect& r_avoid, ImGuiPopupPositionPolicy policy)
{
    ImVec2 base_pos_clamped = ImClamp(ref_pos, r_outer.Min, r_outer.Max - size);
    //GetForegroundDrawList()->AddRect(r_avoid.Min, r_avoid.Max, IM_COL32(255,0,0,255));
    //GetForegroundDrawList()->AddRect(r_outer.Min, r_outer.Max, IM_COL32(0,255,0,255));

    // Combo Box policy (we want a connecting edge)
    if (policy == ImGuiPopupPositionPolicy_ComboBox)
    {
        const ImGuiDir dir_prefered_order[ImGuiDir_COUNT] = { ImGuiDir_Down, ImGuiDir_Right, ImGuiDir_Left, ImGuiDir_Up };
        for (int n = (*last_dir != ImGuiDir_None) ? -1 : 0; n < ImGuiDir_COUNT; n++)
        {
            const ImGuiDir dir = (n == -1) ? *last_dir : dir_prefered_order[n];
            if (n != -1 && dir == *last_dir) // Already tried this direction?
                continue;
            ImVec2 pos;
            if (dir == ImGuiDir_Down)  pos = ImVec2(r_avoid.Min.x, r_avoid.Max.y);          // Below, Toward Right (default)
            if (dir == ImGuiDir_Right) pos = ImVec2(r_avoid.Min.x, r_avoid.Min.y - size.y); // Above, Toward Right
            if (dir == ImGuiDir_Left)  pos = ImVec2(r_avoid.Max.x - size.x, r_avoid.Max.y); // Below, Toward Left
            if (dir == ImGuiDir_Up)    pos = ImVec2(r_avoid.Max.x - size.x, r_avoid.Min.y - size.y); // Above, Toward Left
            if (!r_outer.Contains(ImRect(pos, pos + size)))
                continue;
            *last_dir = dir;
            return pos;
        }
    }

    // Tooltip and Default popup policy
    // (Always first try the direction we used on the last frame, if any)
    if (policy == ImGuiPopupPositionPolicy_Tooltip || policy == ImGuiPopupPositionPolicy_Default)
    {
        const ImGuiDir dir_prefered_order[ImGuiDir_COUNT] = { ImGuiDir_Right, ImGuiDir_Down, ImGuiDir_Up, ImGuiDir_Left };
        for (int n = (*last_dir != ImGuiDir_None) ? -1 : 0; n < ImGuiDir_COUNT; n++)
        {
            const ImGuiDir dir = (n == -1) ? *last_dir : dir_prefered_order[n];
            if (n != -1 && dir == *last_dir) // Already tried this direction?
                continue;

            const float avail_w = (dir == ImGuiDir_Left ? r_avoid.Min.x : r_outer.Max.x) - (dir == ImGuiDir_Right ? r_avoid.Max.x : r_outer.Min.x);
            const float avail_h = (dir == ImGuiDir_Up ? r_avoid.Min.y : r_outer.Max.y) - (dir == ImGuiDir_Down ? r_avoid.Max.y : r_outer.Min.y);

            // If there's not enough room on one axis, there's no point in positioning on a side on this axis (e.g. when not enough width, use a top/bottom position to maximize available width)
            if (avail_w < size.x && (dir == ImGuiDir_Left || dir == ImGuiDir_Right))
                continue;
            if (avail_h < size.y && (dir == ImGuiDir_Up || dir == ImGuiDir_Down))
                continue;

            ImVec2 pos;
            pos.x = (dir == ImGuiDir_Left) ? r_avoid.Min.x - size.x : (dir == ImGuiDir_Right) ? r_avoid.Max.x : base_pos_clamped.x;
            pos.y = (dir == ImGuiDir_Up) ? r_avoid.Min.y - size.y : (dir == ImGuiDir_Down) ? r_avoid.Max.y : base_pos_clamped.y;

            // Clamp top-left corner of popup
            pos.x = ImMax(pos.x, r_outer.Min.x);
            pos.y = ImMax(pos.y, r_outer.Min.y);

            *last_dir = dir;
            return pos;
        }
    }

    // Fallback when not enough room:
    *last_dir = ImGuiDir_None;

    // For tooltip we prefer avoiding the cursor at all cost even if it means that part of the tooltip won't be visible.
    if (policy == ImGuiPopupPositionPolicy_Tooltip)
        return ref_pos + ImVec2(2, 2);

    // Otherwise try to keep within display
    ImVec2 pos = ref_pos;
    pos.x = ImMax(ImMin(pos.x + size.x, r_outer.Max.x) - size.x, r_outer.Min.x);
    pos.y = ImMax(ImMin(pos.y + size.y, r_outer.Max.y) - size.y, r_outer.Min.y);
    return pos;
}

// Note that this is used for popups, which can overlap the non work-area of individual viewports.
ImRect ImGui::GetPopupAllowedExtentRect(ImGuiWindow* window)
{
    ImGuiContext& g = *GImGui;
    ImRect r_screen;
    if (window->ViewportAllowPlatformMonitorExtend >= 0)
    {
        // Extent with be in the frame of reference of the given viewport (so Min is likely to be negative here)
        const ImGuiPlatformMonitor& monitor = g.PlatformIO.Monitors[window->ViewportAllowPlatformMonitorExtend];
        r_screen.Min = monitor.WorkPos;
        r_screen.Max = monitor.WorkPos + monitor.WorkSize;
    }
    else
    {
        // Use the full viewport area (not work area) for popups
        r_screen = window->Viewport->GetMainRect();
    }
    ImVec2 padding = g.Style.DisplaySafeAreaPadding;
    r_screen.Expand(ImVec2((r_screen.GetWidth() > padding.x * 2) ? -padding.x : 0.0f, (r_screen.GetHeight() > padding.y * 2) ? -padding.y : 0.0f));
    return r_screen;
}

ImVec2 ImGui::FindBestWindowPosForPopup(ImGuiWindow* window)
{
    ImGuiContext& g = *GImGui;

    ImRect r_outer = GetPopupAllowedExtentRect(window);
    if (window->Flags & ImGuiWindowFlags_ChildMenu)
    {
        // Child menus typically request _any_ position within the parent menu item, and then we move the new menu outside the parent bounds.
        // This is how we end up with child menus appearing (most-commonly) on the right of the parent menu.
        ImGuiWindow* parent_window = window->ParentWindow;
        float horizontal_overlap = g.Style.ItemInnerSpacing.x; // We want some overlap to convey the relative depth of each menu (currently the amount of overlap is hard-coded to style.ItemSpacing.x).
        ImRect r_avoid;
        if (parent_window->DC.MenuBarAppending)
            r_avoid = ImRect(-FLT_MAX, parent_window->ClipRect.Min.y, FLT_MAX, parent_window->ClipRect.Max.y); // Avoid parent menu-bar. If we wanted multi-line menu-bar, we may instead want to have the calling window setup e.g. a NextWindowData.PosConstraintAvoidRect field
        else
            r_avoid = ImRect(parent_window->Pos.x + horizontal_overlap, -FLT_MAX, parent_window->Pos.x + parent_window->Size.x - horizontal_overlap - parent_window->ScrollbarSizes.x, FLT_MAX);
        return FindBestWindowPosForPopupEx(window->Pos, window->Size, &window->AutoPosLastDirection, r_outer, r_avoid, ImGuiPopupPositionPolicy_Default);
    }
    if (window->Flags & ImGuiWindowFlags_Popup)
    {
        return FindBestWindowPosForPopupEx(window->Pos, window->Size, &window->AutoPosLastDirection, r_outer, ImRect(window->Pos, window->Pos), ImGuiPopupPositionPolicy_Default); // Ideally we'd disable r_avoid here
    }
    if (window->Flags & ImGuiWindowFlags_Tooltip)
    {
        // Position tooltip (always follows mouse + clamp within outer boundaries)
        // Note that drag and drop tooltips are NOT using this path: BeginTooltipEx() manually sets their position.
        // In theory we could handle both cases in same location, but requires a bit of shuffling as drag and drop tooltips are calling SetWindowPos() leading to 'window_pos_set_by_api' being set in Begin()
        IM_ASSERT(g.CurrentWindow == window);
        const float scale = g.Style.MouseCursorScale;
        const ImVec2 ref_pos = NavCalcPreferredRefPos();
        const ImVec2 tooltip_pos = ref_pos + TOOLTIP_DEFAULT_OFFSET * scale;
        ImRect r_avoid;
        if (!g.NavDisableHighlight && g.NavDisableMouseHover && !(g.IO.ConfigFlags & ImGuiConfigFlags_NavEnableSetMousePos))
            r_avoid = ImRect(ref_pos.x - 16, ref_pos.y - 8, ref_pos.x + 16, ref_pos.y + 8);
        else
            r_avoid = ImRect(ref_pos.x - 16, ref_pos.y - 8, ref_pos.x + 24 * scale, ref_pos.y + 24 * scale); // FIXME: Hard-coded based on mouse cursor shape expectation. Exact dimension not very important.
        //GetForegroundDrawList()->AddRect(r_avoid.Min, r_avoid.Max, IM_COL32(255, 0, 255, 255));
        return FindBestWindowPosForPopupEx(tooltip_pos, window->Size, &window->AutoPosLastDirection, r_outer, r_avoid, ImGuiPopupPositionPolicy_Tooltip);
    }
    IM_ASSERT(0);
    return window->Pos;
}

//-----------------------------------------------------------------------------
// [SECTION] KEYBOARD/GAMEPAD NAVIGATION
//-----------------------------------------------------------------------------

// FIXME-NAV: The existence of SetNavID vs SetFocusID vs FocusWindow() needs to be clarified/reworked.
// In our terminology those should be interchangeable, yet right now this is super confusing.
// Those two functions are merely a legacy artifact, so at minimum naming should be clarified.

void ImGui::SetNavWindow(ImGuiWindow* window)
{
    ImGuiContext& g = *GImGui;
    if (g.NavWindow != window)
    {
        IMGUI_DEBUG_LOG_FOCUS("[focus] SetNavWindow(\"%s\")\n", window ? window->Name : "<NULL>");
        g.NavWindow = window;
        g.NavLastValidSelectionUserData = ImGuiSelectionUserData_Invalid;
    }
    g.NavInitRequest = g.NavMoveSubmitted = g.NavMoveScoringItems = false;
    NavUpdateAnyRequestFlag();
}

void ImGui::NavClearPreferredPosForAxis(ImGuiAxis axis)
{
    ImGuiContext& g = *GImGui;
    g.NavWindow->RootWindowForNav->NavPreferredScoringPosRel[g.NavLayer][axis] = FLT_MAX;
}

void ImGui::SetNavID(ImGuiID id, ImGuiNavLayer nav_layer, ImGuiID focus_scope_id, const ImRect& rect_rel)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(g.NavWindow != NULL);
    IM_ASSERT(nav_layer == ImGuiNavLayer_Main || nav_layer == ImGuiNavLayer_Menu);
    g.NavId = id;
    g.NavLayer = nav_layer;
    g.NavFocusScopeId = focus_scope_id;
    g.NavWindow->NavLastIds[nav_layer] = id;
    g.NavWindow->NavRectRel[nav_layer] = rect_rel;

    // Clear preferred scoring position (NavMoveRequestApplyResult() will tend to restore it)
    NavClearPreferredPosForAxis(ImGuiAxis_X);
    NavClearPreferredPosForAxis(ImGuiAxis_Y);
}

void ImGui::SetFocusID(ImGuiID id, ImGuiWindow* window)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(id != 0);

    if (g.NavWindow != window)
       SetNavWindow(window);

    // Assume that SetFocusID() is called in the context where its window->DC.NavLayerCurrent and g.CurrentFocusScopeId are valid.
    // Note that window may be != g.CurrentWindow (e.g. SetFocusID call in InputTextEx for multi-line text)
    const ImGuiNavLayer nav_layer = window->DC.NavLayerCurrent;
    g.NavId = id;
    g.NavLayer = nav_layer;
    g.NavFocusScopeId = g.CurrentFocusScopeId;
    window->NavLastIds[nav_layer] = id;
    if (g.LastItemData.ID == id)
        window->NavRectRel[nav_layer] = WindowRectAbsToRel(window, g.LastItemData.NavRect);

    if (g.ActiveIdSource == ImGuiInputSource_Keyboard || g.ActiveIdSource == ImGuiInputSource_Gamepad)
        g.NavDisableMouseHover = true;
    else
        g.NavDisableHighlight = true;

    // Clear preferred scoring position (NavMoveRequestApplyResult() will tend to restore it)
    NavClearPreferredPosForAxis(ImGuiAxis_X);
    NavClearPreferredPosForAxis(ImGuiAxis_Y);
}

static ImGuiDir ImGetDirQuadrantFromDelta(float dx, float dy)
{
    if (ImFabs(dx) > ImFabs(dy))
        return (dx > 0.0f) ? ImGuiDir_Right : ImGuiDir_Left;
    return (dy > 0.0f) ? ImGuiDir_Down : ImGuiDir_Up;
}

static float inline NavScoreItemDistInterval(float cand_min, float cand_max, float curr_min, float curr_max)
{
    if (cand_max < curr_min)
        return cand_max - curr_min;
    if (curr_max < cand_min)
        return cand_min - curr_max;
    return 0.0f;
}

// Scoring function for gamepad/keyboard directional navigation. Based on https://gist.github.com/rygorous/6981057
static bool ImGui::NavScoreItem(ImGuiNavItemData* result)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    if (g.NavLayer != window->DC.NavLayerCurrent)
        return false;

    // FIXME: Those are not good variables names
    ImRect cand = g.LastItemData.NavRect;   // Current item nav rectangle
    const ImRect curr = g.NavScoringRect;   // Current modified source rect (NB: we've applied Max.x = Min.x in NavUpdate() to inhibit the effect of having varied item width)
    g.NavScoringDebugCount++;

    // When entering through a NavFlattened border, we consider child window items as fully clipped for scoring
    if (window->ParentWindow == g.NavWindow)
    {
        IM_ASSERT((window->Flags | g.NavWindow->Flags) & ImGuiWindowFlags_NavFlattened);
        if (!window->ClipRect.Overlaps(cand))
            return false;
        cand.ClipWithFull(window->ClipRect); // This allows the scored item to not overlap other candidates in the parent window
    }

    // Compute distance between boxes
    // FIXME-NAV: Introducing biases for vertical navigation, needs to be removed.
    float dbx = NavScoreItemDistInterval(cand.Min.x, cand.Max.x, curr.Min.x, curr.Max.x);
    float dby = NavScoreItemDistInterval(ImLerp(cand.Min.y, cand.Max.y, 0.2f), ImLerp(cand.Min.y, cand.Max.y, 0.8f), ImLerp(curr.Min.y, curr.Max.y, 0.2f), ImLerp(curr.Min.y, curr.Max.y, 0.8f)); // Scale down on Y to keep using box-distance for vertically touching items
    if (dby != 0.0f && dbx != 0.0f)
        dbx = (dbx / 1000.0f) + ((dbx > 0.0f) ? +1.0f : -1.0f);
    float dist_box = ImFabs(dbx) + ImFabs(dby);

    // Compute distance between centers (this is off by a factor of 2, but we only compare center distances with each other so it doesn't matter)
    float dcx = (cand.Min.x + cand.Max.x) - (curr.Min.x + curr.Max.x);
    float dcy = (cand.Min.y + cand.Max.y) - (curr.Min.y + curr.Max.y);
    float dist_center = ImFabs(dcx) + ImFabs(dcy); // L1 metric (need this for our connectedness guarantee)

    // Determine which quadrant of 'curr' our candidate item 'cand' lies in based on distance
    ImGuiDir quadrant;
    float dax = 0.0f, day = 0.0f, dist_axial = 0.0f;
    if (dbx != 0.0f || dby != 0.0f)
    {
        // For non-overlapping boxes, use distance between boxes
        dax = dbx;
        day = dby;
        dist_axial = dist_box;
        quadrant = ImGetDirQuadrantFromDelta(dbx, dby);
    }
    else if (dcx != 0.0f || dcy != 0.0f)
    {
        // For overlapping boxes with different centers, use distance between centers
        dax = dcx;
        day = dcy;
        dist_axial = dist_center;
        quadrant = ImGetDirQuadrantFromDelta(dcx, dcy);
    }
    else
    {
        // Degenerate case: two overlapping buttons with same center, break ties arbitrarily (note that LastItemId here is really the _previous_ item order, but it doesn't matter)
        quadrant = (g.LastItemData.ID < g.NavId) ? ImGuiDir_Left : ImGuiDir_Right;
    }

    const ImGuiDir move_dir = g.NavMoveDir;
#if IMGUI_DEBUG_NAV_SCORING
    char buf[200];
    if (g.IO.KeyCtrl) // Hold CTRL to preview score in matching quadrant. CTRL+Arrow to rotate.
    {
        if (quadrant == move_dir)
        {
            ImFormatString(buf, IM_ARRAYSIZE(buf), "%.0f/%.0f", dist_box, dist_center);
            ImDrawList* draw_list = GetForegroundDrawList(window);
            draw_list->AddRectFilled(cand.Min, cand.Max, IM_COL32(255, 0, 0, 80));
            draw_list->AddRectFilled(cand.Min, cand.Min + CalcTextSize(buf), IM_COL32(255, 0, 0, 200));
            draw_list->AddText(cand.Min, IM_COL32(255, 255, 255, 255), buf);
        }
    }
    const bool debug_hovering = IsMouseHoveringRect(cand.Min, cand.Max);
    const bool debug_tty = (g.IO.KeyCtrl && IsKeyPressed(ImGuiKey_Space));
    if (debug_hovering || debug_tty)
    {
        ImFormatString(buf, IM_ARRAYSIZE(buf),
            "d-box    (%7.3f,%7.3f) -> %7.3f\nd-center (%7.3f,%7.3f) -> %7.3f\nd-axial  (%7.3f,%7.3f) -> %7.3f\nnav %c, quadrant %c",
            dbx, dby, dist_box, dcx, dcy, dist_center, dax, day, dist_axial, "-WENS"[move_dir+1], "-WENS"[quadrant+1]);
        if (debug_hovering)
        {
            ImDrawList* draw_list = GetForegroundDrawList(window);
            draw_list->AddRect(curr.Min, curr.Max, IM_COL32(255, 200, 0, 100));
            draw_list->AddRect(cand.Min, cand.Max, IM_COL32(255, 255, 0, 200));
            draw_list->AddRectFilled(cand.Max - ImVec2(4, 4), cand.Max + CalcTextSize(buf) + ImVec2(4, 4), IM_COL32(40, 0, 0, 200));
            draw_list->AddText(cand.Max, ~0U, buf);
        }
        if (debug_tty) { IMGUI_DEBUG_LOG_NAV("id 0x%08X\n%s\n", g.LastItemData.ID, buf); }
    }
#endif

    // Is it in the quadrant we're interested in moving to?
    bool new_best = false;
    if (quadrant == move_dir)
    {
        // Does it beat the current best candidate?
        if (dist_box < result->DistBox)
        {
            result->DistBox = dist_box;
            result->DistCenter = dist_center;
            return true;
        }
        if (dist_box == result->DistBox)
        {
            // Try using distance between center points to break ties
            if (dist_center < result->DistCenter)
            {
                result->DistCenter = dist_center;
                new_best = true;
            }
            else if (dist_center == result->DistCenter)
            {
                // Still tied! we need to be extra-careful to make sure everything gets linked properly. We consistently break ties by symbolically moving "later" items
                // (with higher index) to the right/downwards by an infinitesimal amount since we the current "best" button already (so it must have a lower index),
                // this is fairly easy. This rule ensures that all buttons with dx==dy==0 will end up being linked in order of appearance along the x axis.
                if (((move_dir == ImGuiDir_Up || move_dir == ImGuiDir_Down) ? dby : dbx) < 0.0f) // moving bj to the right/down decreases distance
                    new_best = true;
            }
        }
    }

    // Axial check: if 'curr' has no link at all in some direction and 'cand' lies roughly in that direction, add a tentative link. This will only be kept if no "real" matches
    // are found, so it only augments the graph produced by the above method using extra links. (important, since it doesn't guarantee strong connectedness)
    // This is just to avoid buttons having no links in a particular direction when there's a suitable neighbor. you get good graphs without this too.
    // 2017/09/29: FIXME: This now currently only enabled inside menu bars, ideally we'd disable it everywhere. Menus in particular need to catch failure. For general navigation it feels awkward.
    // Disabling it may lead to disconnected graphs when nodes are very spaced out on different axis. Perhaps consider offering this as an option?
    if (result->DistBox == FLT_MAX && dist_axial < result->DistAxial)  // Check axial match
        if (g.NavLayer == ImGuiNavLayer_Menu && !(g.NavWindow->Flags & ImGuiWindowFlags_ChildMenu))
            if ((move_dir == ImGuiDir_Left && dax < 0.0f) || (move_dir == ImGuiDir_Right && dax > 0.0f) || (move_dir == ImGuiDir_Up && day < 0.0f) || (move_dir == ImGuiDir_Down && day > 0.0f))
            {
                result->DistAxial = dist_axial;
                new_best = true;
            }

    return new_best;
}

static void ImGui::NavApplyItemToResult(ImGuiNavItemData* result)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    result->Window = window;
    result->ID = g.LastItemData.ID;
    result->FocusScopeId = g.CurrentFocusScopeId;
    result->InFlags = g.LastItemData.InFlags;
    result->RectRel = WindowRectAbsToRel(window, g.LastItemData.NavRect);
    if (result->InFlags & ImGuiItemFlags_HasSelectionUserData)
    {
        IM_ASSERT(g.NextItemData.SelectionUserData != ImGuiSelectionUserData_Invalid);
        result->SelectionUserData = g.NextItemData.SelectionUserData; // INTENTIONAL: At this point this field is not cleared in NextItemData. Avoid unnecessary copy to LastItemData.
    }
}

// True when current work location may be scrolled horizontally when moving left / right.
// This is generally always true UNLESS within a column. We don't have a vertical equivalent.
void ImGui::NavUpdateCurrentWindowIsScrollPushableX()
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    window->DC.NavIsScrollPushableX = (g.CurrentTable == NULL && window->DC.CurrentColumns == NULL);
}

// We get there when either NavId == id, or when g.NavAnyRequest is set (which is updated by NavUpdateAnyRequestFlag above)
// This is called after LastItemData is set, but NextItemData is also still valid.
static void ImGui::NavProcessItem()
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    const ImGuiID id = g.LastItemData.ID;
    const ImGuiItemFlags item_flags = g.LastItemData.InFlags;

    // When inside a container that isn't scrollable with Left<>Right, clip NavRect accordingly (#2221)
    if (window->DC.NavIsScrollPushableX == false)
    {
        g.LastItemData.NavRect.Min.x = ImClamp(g.LastItemData.NavRect.Min.x, window->ClipRect.Min.x, window->ClipRect.Max.x);
        g.LastItemData.NavRect.Max.x = ImClamp(g.LastItemData.NavRect.Max.x, window->ClipRect.Min.x, window->ClipRect.Max.x);
    }
    const ImRect nav_bb = g.LastItemData.NavRect;

    // Process Init Request
    if (g.NavInitRequest && g.NavLayer == window->DC.NavLayerCurrent && (item_flags & ImGuiItemFlags_Disabled) == 0)
    {
        // Even if 'ImGuiItemFlags_NoNavDefaultFocus' is on (typically collapse/close button) we record the first ResultId so they can be used as a fallback
        const bool candidate_for_nav_default_focus = (item_flags & ImGuiItemFlags_NoNavDefaultFocus) == 0;
        if (candidate_for_nav_default_focus || g.NavInitResult.ID == 0)
        {
            NavApplyItemToResult(&g.NavInitResult);
        }
        if (candidate_for_nav_default_focus)
        {
            g.NavInitRequest = false; // Found a match, clear request
            NavUpdateAnyRequestFlag();
        }
    }

    // Process Move Request (scoring for navigation)
    // FIXME-NAV: Consider policy for double scoring (scoring from NavScoringRect + scoring from a rect wrapped according to current wrapping policy)
    if (g.NavMoveScoringItems && (item_flags & ImGuiItemFlags_Disabled) == 0)
    {
        const bool is_tabbing = (g.NavMoveFlags & ImGuiNavMoveFlags_IsTabbing) != 0;
        if (is_tabbing)
        {
            NavProcessItemForTabbingRequest(id, item_flags, g.NavMoveFlags);
        }
        else if (g.NavId != id || (g.NavMoveFlags & ImGuiNavMoveFlags_AllowCurrentNavId))
        {
            ImGuiNavItemData* result = (window == g.NavWindow) ? &g.NavMoveResultLocal : &g.NavMoveResultOther;
            if (NavScoreItem(result))
                NavApplyItemToResult(result);

            // Features like PageUp/PageDown need to maintain a separate score for the visible set of items.
            const float VISIBLE_RATIO = 0.70f;
            if ((g.NavMoveFlags & ImGuiNavMoveFlags_AlsoScoreVisibleSet) && window->ClipRect.Overlaps(nav_bb))
                if (ImClamp(nav_bb.Max.y, window->ClipRect.Min.y, window->ClipRect.Max.y) - ImClamp(nav_bb.Min.y, window->ClipRect.Min.y, window->ClipRect.Max.y) >= (nav_bb.Max.y - nav_bb.Min.y) * VISIBLE_RATIO)
                    if (NavScoreItem(&g.NavMoveResultLocalVisible))
                        NavApplyItemToResult(&g.NavMoveResultLocalVisible);
        }
    }

    // Update information for currently focused/navigated item
    if (g.NavId == id)
    {
        if (g.NavWindow != window)
            SetNavWindow(window); // Always refresh g.NavWindow, because some operations such as FocusItem() may not have a window.
        g.NavLayer = window->DC.NavLayerCurrent;
        g.NavFocusScopeId = g.CurrentFocusScopeId;
        g.NavIdIsAlive = true;
        if (g.LastItemData.InFlags & ImGuiItemFlags_HasSelectionUserData)
        {
            IM_ASSERT(g.NextItemData.SelectionUserData != ImGuiSelectionUserData_Invalid);
            g.NavLastValidSelectionUserData = g.NextItemData.SelectionUserData; // INTENTIONAL: At this point this field is not cleared in NextItemData. Avoid unnecessary copy to LastItemData.
        }
        window->NavRectRel[window->DC.NavLayerCurrent] = WindowRectAbsToRel(window, nav_bb); // Store item bounding box (relative to window position)
    }
}

// Handle "scoring" of an item for a tabbing/focusing request initiated by NavUpdateCreateTabbingRequest().
// Note that SetKeyboardFocusHere() API calls are considered tabbing requests!
// - Case 1: no nav/active id:    set result to first eligible item, stop storing.
// - Case 2: tab forward:         on ref id set counter, on counter elapse store result
// - Case 3: tab forward wrap:    set result to first eligible item (preemptively), on ref id set counter, on next frame if counter hasn't elapsed store result. // FIXME-TABBING: Could be done as a next-frame forwarded request
// - Case 4: tab backward:        store all results, on ref id pick prev, stop storing
// - Case 5: tab backward wrap:   store all results, on ref id if no result keep storing until last // FIXME-TABBING: Could be done as next-frame forwarded requested
void ImGui::NavProcessItemForTabbingRequest(ImGuiID id, ImGuiItemFlags item_flags, ImGuiNavMoveFlags move_flags)
{
    ImGuiContext& g = *GImGui;

    if ((move_flags & ImGuiNavMoveFlags_FocusApi) == 0)
        if (g.NavLayer != g.CurrentWindow->DC.NavLayerCurrent)
            return;

    // - Can always land on an item when using API call.
    // - Tabbing with _NavEnableKeyboard (space/enter/arrows): goes through every item.
    // - Tabbing without _NavEnableKeyboard: goes through inputable items only.
    bool can_stop;
    if (move_flags & ImGuiNavMoveFlags_FocusApi)
        can_stop = true;
    else
        can_stop = (item_flags & ImGuiItemFlags_NoTabStop) == 0 && ((g.IO.ConfigFlags & ImGuiConfigFlags_NavEnableKeyboard) || (item_flags & ImGuiItemFlags_Inputable));

    // Always store in NavMoveResultLocal (unlike directional request which uses NavMoveResultOther on sibling/flattened windows)
    ImGuiNavItemData* result = &g.NavMoveResultLocal;
    if (g.NavTabbingDir == +1)
    {
        // Tab Forward or SetKeyboardFocusHere() with >= 0
        if (can_stop && g.NavTabbingResultFirst.ID == 0)
            NavApplyItemToResult(&g.NavTabbingResultFirst);
        if (can_stop && g.NavTabbingCounter > 0 && --g.NavTabbingCounter == 0)
            NavMoveRequestResolveWithLastItem(result);
        else if (g.NavId == id)
            g.NavTabbingCounter = 1;
    }
    else if (g.NavTabbingDir == -1)
    {
        // Tab Backward
        if (g.NavId == id)
        {
            if (result->ID)
            {
                g.NavMoveScoringItems = false;
                NavUpdateAnyRequestFlag();
            }
        }
        else if (can_stop)
        {
            // Keep applying until reaching NavId
            NavApplyItemToResult(result);
        }
    }
    else if (g.NavTabbingDir == 0)
    {
        if (can_stop && g.NavId == id)
            NavMoveRequestResolveWithLastItem(result);
        if (can_stop && g.NavTabbingResultFirst.ID == 0) // Tab init
            NavApplyItemToResult(&g.NavTabbingResultFirst);
    }
}

bool ImGui::NavMoveRequestButNoResultYet()
{
    ImGuiContext& g = *GImGui;
    return g.NavMoveScoringItems && g.NavMoveResultLocal.ID == 0 && g.NavMoveResultOther.ID == 0;
}

// FIXME: ScoringRect is not set
void ImGui::NavMoveRequestSubmit(ImGuiDir move_dir, ImGuiDir clip_dir, ImGuiNavMoveFlags move_flags, ImGuiScrollFlags scroll_flags)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(g.NavWindow != NULL);

    if (move_flags & ImGuiNavMoveFlags_IsTabbing)
        move_flags |= ImGuiNavMoveFlags_AllowCurrentNavId;

    g.NavMoveSubmitted = g.NavMoveScoringItems = true;
    g.NavMoveDir = move_dir;
    g.NavMoveDirForDebug = move_dir;
    g.NavMoveClipDir = clip_dir;
    g.NavMoveFlags = move_flags;
    g.NavMoveScrollFlags = scroll_flags;
    g.NavMoveForwardToNextFrame = false;
    g.NavMoveKeyMods = (move_flags & ImGuiNavMoveFlags_FocusApi) ? 0 : g.IO.KeyMods;
    g.NavMoveResultLocal.Clear();
    g.NavMoveResultLocalVisible.Clear();
    g.NavMoveResultOther.Clear();
    g.NavTabbingCounter = 0;
    g.NavTabbingResultFirst.Clear();
    NavUpdateAnyRequestFlag();
}

void ImGui::NavMoveRequestResolveWithLastItem(ImGuiNavItemData* result)
{
    ImGuiContext& g = *GImGui;
    g.NavMoveScoringItems = false; // Ensure request doesn't need more processing
    NavApplyItemToResult(result);
    NavUpdateAnyRequestFlag();
}

// Called by TreePop() to implement ImGuiTreeNodeFlags_NavLeftJumpsBackHere
void ImGui::NavMoveRequestResolveWithPastTreeNode(ImGuiNavItemData* result, ImGuiNavTreeNodeData* tree_node_data)
{
    ImGuiContext& g = *GImGui;
    g.NavMoveScoringItems = false;
    g.LastItemData.ID = tree_node_data->ID;
    g.LastItemData.InFlags = tree_node_data->InFlags & ~ImGuiItemFlags_HasSelectionUserData; // Losing SelectionUserData, recovered next-frame (cheaper).
    g.LastItemData.NavRect = tree_node_data->NavRect;
    NavApplyItemToResult(result); // Result this instead of implementing a NavApplyPastTreeNodeToResult()
    NavClearPreferredPosForAxis(ImGuiAxis_Y);
    NavUpdateAnyRequestFlag();
}

void ImGui::NavMoveRequestCancel()
{
    ImGuiContext& g = *GImGui;
    g.NavMoveSubmitted = g.NavMoveScoringItems = false;
    NavUpdateAnyRequestFlag();
}

// Forward will reuse the move request again on the next frame (generally with modifications done to it)
void ImGui::NavMoveRequestForward(ImGuiDir move_dir, ImGuiDir clip_dir, ImGuiNavMoveFlags move_flags, ImGuiScrollFlags scroll_flags)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(g.NavMoveForwardToNextFrame == false);
    NavMoveRequestCancel();
    g.NavMoveForwardToNextFrame = true;
    g.NavMoveDir = move_dir;
    g.NavMoveClipDir = clip_dir;
    g.NavMoveFlags = move_flags | ImGuiNavMoveFlags_Forwarded;
    g.NavMoveScrollFlags = scroll_flags;
}

// Navigation wrap-around logic is delayed to the end of the frame because this operation is only valid after entire
// popup is assembled and in case of appended popups it is not clear which EndPopup() call is final.
void ImGui::NavMoveRequestTryWrapping(ImGuiWindow* window, ImGuiNavMoveFlags wrap_flags)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT((wrap_flags & ImGuiNavMoveFlags_WrapMask_ ) != 0 && (wrap_flags & ~ImGuiNavMoveFlags_WrapMask_) == 0); // Call with _WrapX, _WrapY, _LoopX, _LoopY

    // In theory we should test for NavMoveRequestButNoResultYet() but there's no point doing it:
    // as NavEndFrame() will do the same test. It will end up calling NavUpdateCreateWrappingRequest().
    if (g.NavWindow == window && g.NavMoveScoringItems && g.NavLayer == ImGuiNavLayer_Main)
        g.NavMoveFlags = (g.NavMoveFlags & ~ImGuiNavMoveFlags_WrapMask_) | wrap_flags;
}

// FIXME: This could be replaced by updating a frame number in each window when (window == NavWindow) and (NavLayer == 0).
// This way we could find the last focused window among our children. It would be much less confusing this way?
static void ImGui::NavSaveLastChildNavWindowIntoParent(ImGuiWindow* nav_window)
{
    ImGuiWindow* parent = nav_window;
    while (parent && parent->RootWindow != parent && (parent->Flags & (ImGuiWindowFlags_Popup | ImGuiWindowFlags_ChildMenu)) == 0)
        parent = parent->ParentWindow;
    if (parent && parent != nav_window)
        parent->NavLastChildNavWindow = nav_window;
}

// Restore the last focused child.
// Call when we are expected to land on the Main Layer (0) after FocusWindow()
static ImGuiWindow* ImGui::NavRestoreLastChildNavWindow(ImGuiWindow* window)
{
    if (window->NavLastChildNavWindow && window->NavLastChildNavWindow->WasActive)
        return window->NavLastChildNavWindow;
    if (window->DockNodeAsHost && window->DockNodeAsHost->TabBar)
        if (ImGuiTabItem* tab = TabBarFindMostRecentlySelectedTabForActiveWindow(window->DockNodeAsHost->TabBar))
            return tab->Window;
    return window;
}

void ImGui::NavRestoreLayer(ImGuiNavLayer layer)
{
    ImGuiContext& g = *GImGui;
    if (layer == ImGuiNavLayer_Main)
    {
        ImGuiWindow* prev_nav_window = g.NavWindow;
        g.NavWindow = NavRestoreLastChildNavWindow(g.NavWindow);    // FIXME-NAV: Should clear ongoing nav requests?
        g.NavLastValidSelectionUserData = ImGuiSelectionUserData_Invalid;
        if (prev_nav_window)
            IMGUI_DEBUG_LOG_FOCUS("[focus] NavRestoreLayer: from \"%s\" to SetNavWindow(\"%s\")\n", prev_nav_window->Name, g.NavWindow->Name);
    }
    ImGuiWindow* window = g.NavWindow;
    if (window->NavLastIds[layer] != 0)
    {
        SetNavID(window->NavLastIds[layer], layer, 0, window->NavRectRel[layer]);
    }
    else
    {
        g.NavLayer = layer;
        NavInitWindow(window, true);
    }
}

void ImGui::NavRestoreHighlightAfterMove()
{
    ImGuiContext& g = *GImGui;
    g.NavDisableHighlight = false;
    g.NavDisableMouseHover = g.NavMousePosDirty = true;
}

static inline void ImGui::NavUpdateAnyRequestFlag()
{
    ImGuiContext& g = *GImGui;
    g.NavAnyRequest = g.NavMoveScoringItems || g.NavInitRequest || (IMGUI_DEBUG_NAV_SCORING && g.NavWindow != NULL);
    if (g.NavAnyRequest)
        IM_ASSERT(g.NavWindow != NULL);
}

// This needs to be called before we submit any widget (aka in or before Begin)
void ImGui::NavInitWindow(ImGuiWindow* window, bool force_reinit)
{
    // FIXME: ChildWindow test here is wrong for docking
    ImGuiContext& g = *GImGui;
    IM_ASSERT(window == g.NavWindow);

    if (window->Flags & ImGuiWindowFlags_NoNavInputs)
    {
        g.NavId = 0;
        g.NavFocusScopeId = window->NavRootFocusScopeId;
        return;
    }

    bool init_for_nav = false;
    if (window == window->RootWindow || (window->Flags & ImGuiWindowFlags_Popup) || (window->NavLastIds[0] == 0) || force_reinit)
        init_for_nav = true;
    IMGUI_DEBUG_LOG_NAV("[nav] NavInitRequest: from NavInitWindow(), init_for_nav=%d, window=\"%s\", layer=%d\n", init_for_nav, window->Name, g.NavLayer);
    if (init_for_nav)
    {
        SetNavID(0, g.NavLayer, window->NavRootFocusScopeId, ImRect());
        g.NavInitRequest = true;
        g.NavInitRequestFromMove = false;
        g.NavInitResult.ID = 0;
        NavUpdateAnyRequestFlag();
    }
    else
    {
        g.NavId = window->NavLastIds[0];
        g.NavFocusScopeId = window->NavRootFocusScopeId;
    }
}

static ImVec2 ImGui::NavCalcPreferredRefPos()
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.NavWindow;
    if (g.NavDisableHighlight || !g.NavDisableMouseHover || !window)
    {
        // Mouse (we need a fallback in case the mouse becomes invalid after being used)
        // The +1.0f offset when stored by OpenPopupEx() allows reopening this or another popup (same or another mouse button) while not moving the mouse, it is pretty standard.
        // In theory we could move that +1.0f offset in OpenPopupEx()
        ImVec2 p = IsMousePosValid(&g.IO.MousePos) ? g.IO.MousePos : g.MouseLastValidPos;
        return ImVec2(p.x + 1.0f, p.y);
    }
    else
    {
        // When navigation is active and mouse is disabled, pick a position around the bottom left of the currently navigated item
        // Take account of upcoming scrolling (maybe set mouse pos should be done in EndFrame?)
        ImRect rect_rel = WindowRectRelToAbs(window, window->NavRectRel[g.NavLayer]);
        if (window->LastFrameActive != g.FrameCount && (window->ScrollTarget.x != FLT_MAX || window->ScrollTarget.y != FLT_MAX))
        {
            ImVec2 next_scroll = CalcNextScrollFromScrollTargetAndClamp(window);
            rect_rel.Translate(window->Scroll - next_scroll);
        }
        ImVec2 pos = ImVec2(rect_rel.Min.x + ImMin(g.Style.FramePadding.x * 4, rect_rel.GetWidth()), rect_rel.Max.y - ImMin(g.Style.FramePadding.y, rect_rel.GetHeight()));
        ImGuiViewport* viewport = window->Viewport;
        return ImTrunc(ImClamp(pos, viewport->Pos, viewport->Pos + viewport->Size)); // ImTrunc() is important because non-integer mouse position application in backend might be lossy and result in undesirable non-zero delta.
    }
}

float ImGui::GetNavTweakPressedAmount(ImGuiAxis axis)
{
    ImGuiContext& g = *GImGui;
    float repeat_delay, repeat_rate;
    GetTypematicRepeatRate(ImGuiInputFlags_RepeatRateNavTweak, &repeat_delay, &repeat_rate);

    ImGuiKey key_less, key_more;
    if (g.NavInputSource == ImGuiInputSource_Gamepad)
    {
        key_less = (axis == ImGuiAxis_X) ? ImGuiKey_GamepadDpadLeft : ImGuiKey_GamepadDpadUp;
        key_more = (axis == ImGuiAxis_X) ? ImGuiKey_GamepadDpadRight : ImGuiKey_GamepadDpadDown;
    }
    else
    {
        key_less = (axis == ImGuiAxis_X) ? ImGuiKey_LeftArrow : ImGuiKey_UpArrow;
        key_more = (axis == ImGuiAxis_X) ? ImGuiKey_RightArrow : ImGuiKey_DownArrow;
    }
    float amount = (float)GetKeyPressedAmount(key_more, repeat_delay, repeat_rate) - (float)GetKeyPressedAmount(key_less, repeat_delay, repeat_rate);
    if (amount != 0.0f && IsKeyDown(key_less) && IsKeyDown(key_more)) // Cancel when opposite directions are held, regardless of repeat phase
        amount = 0.0f;
    return amount;
}

static void ImGui::NavUpdate()
{
    ImGuiContext& g = *GImGui;
    ImGuiIO& io = g.IO;

    io.WantSetMousePos = false;
    //if (g.NavScoringDebugCount > 0) IMGUI_DEBUG_LOG_NAV("[nav] NavScoringDebugCount %d for '%s' layer %d (Init:%d, Move:%d)\n", g.NavScoringDebugCount, g.NavWindow ? g.NavWindow->Name : "NULL", g.NavLayer, g.NavInitRequest || g.NavInitResultId != 0, g.NavMoveRequest);

    // Set input source based on which keys are last pressed (as some features differs when used with Gamepad vs Keyboard)
    // FIXME-NAV: Now that keys are separated maybe we can get rid of NavInputSource?
    const bool nav_gamepad_active = (io.ConfigFlags & ImGuiConfigFlags_NavEnableGamepad) != 0 && (io.BackendFlags & ImGuiBackendFlags_HasGamepad) != 0;
    const ImGuiKey nav_gamepad_keys_to_change_source[] = { ImGuiKey_GamepadFaceRight, ImGuiKey_GamepadFaceLeft, ImGuiKey_GamepadFaceUp, ImGuiKey_GamepadFaceDown, ImGuiKey_GamepadDpadRight, ImGuiKey_GamepadDpadLeft, ImGuiKey_GamepadDpadUp, ImGuiKey_GamepadDpadDown };
    if (nav_gamepad_active)
        for (ImGuiKey key : nav_gamepad_keys_to_change_source)
            if (IsKeyDown(key))
                g.NavInputSource = ImGuiInputSource_Gamepad;
    const bool nav_keyboard_active = (io.ConfigFlags & ImGuiConfigFlags_NavEnableKeyboard) != 0;
    const ImGuiKey nav_keyboard_keys_to_change_source[] = { ImGuiKey_Space, ImGuiKey_Enter, ImGuiKey_Escape, ImGuiKey_RightArrow, ImGuiKey_LeftArrow, ImGuiKey_UpArrow, ImGuiKey_DownArrow };
    if (nav_keyboard_active)
        for (ImGuiKey key : nav_keyboard_keys_to_change_source)
            if (IsKeyDown(key))
                g.NavInputSource = ImGuiInputSource_Keyboard;

    // Process navigation init request (select first/default focus)
    g.NavJustMovedToId = 0;
    if (g.NavInitResult.ID != 0)
        NavInitRequestApplyResult();
    g.NavInitRequest = false;
    g.NavInitRequestFromMove = false;
    g.NavInitResult.ID = 0;

    // Process navigation move request
    if (g.NavMoveSubmitted)
        NavMoveRequestApplyResult();
    g.NavTabbingCounter = 0;
    g.NavMoveSubmitted = g.NavMoveScoringItems = false;

    // Schedule mouse position update (will be done at the bottom of this function, after 1) processing all move requests and 2) updating scrolling)
    bool set_mouse_pos = false;
    if (g.NavMousePosDirty && g.NavIdIsAlive)
        if (!g.NavDisableHighlight && g.NavDisableMouseHover && g.NavWindow)
            set_mouse_pos = true;
    g.NavMousePosDirty = false;
    IM_ASSERT(g.NavLayer == ImGuiNavLayer_Main || g.NavLayer == ImGuiNavLayer_Menu);

    // Store our return window (for returning from Menu Layer to Main Layer) and clear it as soon as we step back in our own Layer 0
    if (g.NavWindow)
        NavSaveLastChildNavWindowIntoParent(g.NavWindow);
    if (g.NavWindow && g.NavWindow->NavLastChildNavWindow != NULL && g.NavLayer == ImGuiNavLayer_Main)
        g.NavWindow->NavLastChildNavWindow = NULL;

    // Update CTRL+TAB and Windowing features (hold Square to move/resize/etc.)
    NavUpdateWindowing();

    // Set output flags for user application
    io.NavActive = (nav_keyboard_active || nav_gamepad_active) && g.NavWindow && !(g.NavWindow->Flags & ImGuiWindowFlags_NoNavInputs);
    io.NavVisible = (io.NavActive && g.NavId != 0 && !g.NavDisableHighlight) || (g.NavWindowingTarget != NULL);

    // Process NavCancel input (to close a popup, get back to parent, clear focus)
    NavUpdateCancelRequest();

    // Process manual activation request
    g.NavActivateId = g.NavActivateDownId = g.NavActivatePressedId = 0;
    g.NavActivateFlags = ImGuiActivateFlags_None;
    if (g.NavId != 0 && !g.NavDisableHighlight && !g.NavWindowingTarget && g.NavWindow && !(g.NavWindow->Flags & ImGuiWindowFlags_NoNavInputs))
    {
        const bool activate_down = (nav_keyboard_active && IsKeyDown(ImGuiKey_Space)) || (nav_gamepad_active && IsKeyDown(ImGuiKey_NavGamepadActivate));
        const bool activate_pressed = activate_down && ((nav_keyboard_active && IsKeyPressed(ImGuiKey_Space, false)) || (nav_gamepad_active && IsKeyPressed(ImGuiKey_NavGamepadActivate, false)));
        const bool input_down = (nav_keyboard_active && IsKeyDown(ImGuiKey_Enter)) || (nav_gamepad_active && IsKeyDown(ImGuiKey_NavGamepadInput));
        const bool input_pressed = input_down && ((nav_keyboard_active && IsKeyPressed(ImGuiKey_Enter, false)) || (nav_gamepad_active && IsKeyPressed(ImGuiKey_NavGamepadInput, false)));
        if (g.ActiveId == 0 && activate_pressed)
        {
            g.NavActivateId = g.NavId;
            g.NavActivateFlags = ImGuiActivateFlags_PreferTweak;
        }
        if ((g.ActiveId == 0 || g.ActiveId == g.NavId) && input_pressed)
        {
            g.NavActivateId = g.NavId;
            g.NavActivateFlags = ImGuiActivateFlags_PreferInput;
        }
        if ((g.ActiveId == 0 || g.ActiveId == g.NavId) && (activate_down || input_down))
            g.NavActivateDownId = g.NavId;
        if ((g.ActiveId == 0 || g.ActiveId == g.NavId) && (activate_pressed || input_pressed))
            g.NavActivatePressedId = g.NavId;
    }
    if (g.NavWindow && (g.NavWindow->Flags & ImGuiWindowFlags_NoNavInputs))
        g.NavDisableHighlight = true;
    if (g.NavActivateId != 0)
        IM_ASSERT(g.NavActivateDownId == g.NavActivateId);

    // Process programmatic activation request
    // FIXME-NAV: Those should eventually be queued (unlike focus they don't cancel each others)
    if (g.NavNextActivateId != 0)
    {
        g.NavActivateId = g.NavActivateDownId = g.NavActivatePressedId = g.NavNextActivateId;
        g.NavActivateFlags = g.NavNextActivateFlags;
    }
    g.NavNextActivateId = 0;

    // Process move requests
    NavUpdateCreateMoveRequest();
    if (g.NavMoveDir == ImGuiDir_None)
        NavUpdateCreateTabbingRequest();
    NavUpdateAnyRequestFlag();
    g.NavIdIsAlive = false;

    // Scrolling
    if (g.NavWindow && !(g.NavWindow->Flags & ImGuiWindowFlags_NoNavInputs) && !g.NavWindowingTarget)
    {
        // *Fallback* manual-scroll with Nav directional keys when window has no navigable item
        ImGuiWindow* window = g.NavWindow;
        const float scroll_speed = IM_ROUND(window->CalcFontSize() * 100 * io.DeltaTime); // We need round the scrolling speed because sub-pixel scroll isn't reliably supported.
        const ImGuiDir move_dir = g.NavMoveDir;
        if (window->DC.NavLayersActiveMask == 0x00 && window->DC.NavWindowHasScrollY && move_dir != ImGuiDir_None)
        {
            if (move_dir == ImGuiDir_Left || move_dir == ImGuiDir_Right)
                SetScrollX(window, ImTrunc(window->Scroll.x + ((move_dir == ImGuiDir_Left) ? -1.0f : +1.0f) * scroll_speed));
            if (move_dir == ImGuiDir_Up || move_dir == ImGuiDir_Down)
                SetScrollY(window, ImTrunc(window->Scroll.y + ((move_dir == ImGuiDir_Up) ? -1.0f : +1.0f) * scroll_speed));
        }

        // *Normal* Manual scroll with LStick
        // Next movement request will clamp the NavId reference rectangle to the visible area, so navigation will resume within those bounds.
        if (nav_gamepad_active)
        {
            const ImVec2 scroll_dir = GetKeyMagnitude2d(ImGuiKey_GamepadLStickLeft, ImGuiKey_GamepadLStickRight, ImGuiKey_GamepadLStickUp, ImGuiKey_GamepadLStickDown);
            const float tweak_factor = IsKeyDown(ImGuiKey_NavGamepadTweakSlow) ? 1.0f / 10.0f : IsKeyDown(ImGuiKey_NavGamepadTweakFast) ? 10.0f : 1.0f;
            if (scroll_dir.x != 0.0f && window->ScrollbarX)
                SetScrollX(window, ImTrunc(window->Scroll.x + scroll_dir.x * scroll_speed * tweak_factor));
            if (scroll_dir.y != 0.0f)
                SetScrollY(window, ImTrunc(window->Scroll.y + scroll_dir.y * scroll_speed * tweak_factor));
        }
    }

    // Always prioritize mouse highlight if navigation is disabled
    if (!nav_keyboard_active && !nav_gamepad_active)
    {
        g.NavDisableHighlight = true;
        g.NavDisableMouseHover = set_mouse_pos = false;
    }

    // Update mouse position if requested
    // (This will take into account the possibility that a Scroll was queued in the window to offset our absolute mouse position before scroll has been applied)
    if (set_mouse_pos && (io.ConfigFlags & ImGuiConfigFlags_NavEnableSetMousePos) && (io.BackendFlags & ImGuiBackendFlags_HasSetMousePos))
        TeleportMousePos(NavCalcPreferredRefPos());

    // [DEBUG]
    g.NavScoringDebugCount = 0;
#if IMGUI_DEBUG_NAV_RECTS
    if (ImGuiWindow* debug_window = g.NavWindow)
    {
        ImDrawList* draw_list = GetForegroundDrawList(debug_window);
        int layer = g.NavLayer; /* for (int layer = 0; layer < 2; layer++)*/ { ImRect r = WindowRectRelToAbs(debug_window, debug_window->NavRectRel[layer]); draw_list->AddRect(r.Min, r.Max, IM_COL32(255, 200, 0, 255)); }
        //if (1) { ImU32 col = (!debug_window->Hidden) ? IM_COL32(255,0,255,255) : IM_COL32(255,0,0,255); ImVec2 p = NavCalcPreferredRefPos(); char buf[32]; ImFormatString(buf, 32, "%d", g.NavLayer); draw_list->AddCircleFilled(p, 3.0f, col); draw_list->AddText(NULL, 13.0f, p + ImVec2(8,-4), col, buf); }
    }
#endif
}

void ImGui::NavInitRequestApplyResult()
{
    // In very rare cases g.NavWindow may be null (e.g. clearing focus after requesting an init request, which does happen when releasing Alt while clicking on void)
    ImGuiContext& g = *GImGui;
    if (!g.NavWindow)
        return;

    ImGuiNavItemData* result = &g.NavInitResult;
    if (g.NavId != result->ID)
    {
        g.NavJustMovedToId = result->ID;
        g.NavJustMovedToFocusScopeId = result->FocusScopeId;
        g.NavJustMovedToKeyMods = 0;
    }

    // Apply result from previous navigation init request (will typically select the first item, unless SetItemDefaultFocus() has been called)
    // FIXME-NAV: On _NavFlattened windows, g.NavWindow will only be updated during subsequent frame. Not a problem currently.
    IMGUI_DEBUG_LOG_NAV("[nav] NavInitRequest: ApplyResult: NavID 0x%08X in Layer %d Window \"%s\"\n", result->ID, g.NavLayer, g.NavWindow->Name);
    SetNavID(result->ID, g.NavLayer, result->FocusScopeId, result->RectRel);
    g.NavIdIsAlive = true; // Mark as alive from previous frame as we got a result
    if (result->SelectionUserData != ImGuiSelectionUserData_Invalid)
        g.NavLastValidSelectionUserData = result->SelectionUserData;
    if (g.NavInitRequestFromMove)
        NavRestoreHighlightAfterMove();
}

// Bias scoring rect ahead of scoring + update preferred pos (if missing) using source position
static void NavBiasScoringRect(ImRect& r, ImVec2& preferred_pos_rel, ImGuiDir move_dir, ImGuiNavMoveFlags move_flags)
{
    // Bias initial rect
    ImGuiContext& g = *GImGui;
    const ImVec2 rel_to_abs_offset = g.NavWindow->DC.CursorStartPos;

    // Initialize bias on departure if we don't have any. So mouse-click + arrow will record bias.
    // - We default to L/U bias, so moving down from a large source item into several columns will land on left-most column.
    // - But each successful move sets new bias on one axis, only cleared when using mouse.
    if ((move_flags & ImGuiNavMoveFlags_Forwarded) == 0)
    {
        if (preferred_pos_rel.x == FLT_MAX)
            preferred_pos_rel.x = ImMin(r.Min.x + 1.0f, r.Max.x) - rel_to_abs_offset.x;
        if (preferred_pos_rel.y == FLT_MAX)
            preferred_pos_rel.y = r.GetCenter().y - rel_to_abs_offset.y;
    }

    // Apply general bias on the other axis
    if ((move_dir == ImGuiDir_Up || move_dir == ImGuiDir_Down) && preferred_pos_rel.x != FLT_MAX)
        r.Min.x = r.Max.x = preferred_pos_rel.x + rel_to_abs_offset.x;
    else if ((move_dir == ImGuiDir_Left || move_dir == ImGuiDir_Right) && preferred_pos_rel.y != FLT_MAX)
        r.Min.y = r.Max.y = preferred_pos_rel.y + rel_to_abs_offset.y;
}

void ImGui::NavUpdateCreateMoveRequest()
{
    ImGuiContext& g = *GImGui;
    ImGuiIO& io = g.IO;
    ImGuiWindow* window = g.NavWindow;
    const bool nav_gamepad_active = (io.ConfigFlags & ImGuiConfigFlags_NavEnableGamepad) != 0 && (io.BackendFlags & ImGuiBackendFlags_HasGamepad) != 0;
    const bool nav_keyboard_active = (io.ConfigFlags & ImGuiConfigFlags_NavEnableKeyboard) != 0;

    if (g.NavMoveForwardToNextFrame && window != NULL)
    {
        // Forwarding previous request (which has been modified, e.g. wrap around menus rewrite the requests with a starting rectangle at the other side of the window)
        // (preserve most state, which were already set by the NavMoveRequestForward() function)
        IM_ASSERT(g.NavMoveDir != ImGuiDir_None && g.NavMoveClipDir != ImGuiDir_None);
        IM_ASSERT(g.NavMoveFlags & ImGuiNavMoveFlags_Forwarded);
        IMGUI_DEBUG_LOG_NAV("[nav] NavMoveRequestForward %d\n", g.NavMoveDir);
    }
    else
    {
        // Initiate directional inputs request
        g.NavMoveDir = ImGuiDir_None;
        g.NavMoveFlags = ImGuiNavMoveFlags_None;
        g.NavMoveScrollFlags = ImGuiScrollFlags_None;
        if (window && !g.NavWindowingTarget && !(window->Flags & ImGuiWindowFlags_NoNavInputs))
        {
            const ImGuiInputFlags repeat_mode = ImGuiInputFlags_Repeat | (ImGuiInputFlags)ImGuiInputFlags_RepeatRateNavMove;
            if (!IsActiveIdUsingNavDir(ImGuiDir_Left)  && ((nav_gamepad_active && IsKeyPressed(ImGuiKey_GamepadDpadLeft,  ImGuiKeyOwner_None, repeat_mode)) || (nav_keyboard_active && IsKeyPressed(ImGuiKey_LeftArrow,  ImGuiKeyOwner_None, repeat_mode)))) { g.NavMoveDir = ImGuiDir_Left; }
            if (!IsActiveIdUsingNavDir(ImGuiDir_Right) && ((nav_gamepad_active && IsKeyPressed(ImGuiKey_GamepadDpadRight, ImGuiKeyOwner_None, repeat_mode)) || (nav_keyboard_active && IsKeyPressed(ImGuiKey_RightArrow, ImGuiKeyOwner_None, repeat_mode)))) { g.NavMoveDir = ImGuiDir_Right; }
            if (!IsActiveIdUsingNavDir(ImGuiDir_Up)    && ((nav_gamepad_active && IsKeyPressed(ImGuiKey_GamepadDpadUp,    ImGuiKeyOwner_None, repeat_mode)) || (nav_keyboard_active && IsKeyPressed(ImGuiKey_UpArrow,    ImGuiKeyOwner_None, repeat_mode)))) { g.NavMoveDir = ImGuiDir_Up; }
            if (!IsActiveIdUsingNavDir(ImGuiDir_Down)  && ((nav_gamepad_active && IsKeyPressed(ImGuiKey_GamepadDpadDown,  ImGuiKeyOwner_None, repeat_mode)) || (nav_keyboard_active && IsKeyPressed(ImGuiKey_DownArrow,  ImGuiKeyOwner_None, repeat_mode)))) { g.NavMoveDir = ImGuiDir_Down; }
        }
        g.NavMoveClipDir = g.NavMoveDir;
        g.NavScoringNoClipRect = ImRect(+FLT_MAX, +FLT_MAX, -FLT_MAX, -FLT_MAX);
    }

    // Update PageUp/PageDown/Home/End scroll
    // FIXME-NAV: Consider enabling those keys even without the master ImGuiConfigFlags_NavEnableKeyboard flag?
    float scoring_rect_offset_y = 0.0f;
    if (window && g.NavMoveDir == ImGuiDir_None && nav_keyboard_active)
        scoring_rect_offset_y = NavUpdatePageUpPageDown();
    if (scoring_rect_offset_y != 0.0f)
    {
        g.NavScoringNoClipRect = window->InnerRect;
        g.NavScoringNoClipRect.TranslateY(scoring_rect_offset_y);
    }

    // [DEBUG] Always send a request when holding CTRL. Hold CTRL + Arrow change the direction.
#if IMGUI_DEBUG_NAV_SCORING
    //if (io.KeyCtrl && IsKeyPressed(ImGuiKey_C))
    //    g.NavMoveDirForDebug = (ImGuiDir)((g.NavMoveDirForDebug + 1) & 3);
    if (io.KeyCtrl)
    {
        if (g.NavMoveDir == ImGuiDir_None)
            g.NavMoveDir = g.NavMoveDirForDebug;
        g.NavMoveClipDir = g.NavMoveDir;
        g.NavMoveFlags |= ImGuiNavMoveFlags_DebugNoResult;
    }
#endif

    // Submit
    g.NavMoveForwardToNextFrame = false;
    if (g.NavMoveDir != ImGuiDir_None)
        NavMoveRequestSubmit(g.NavMoveDir, g.NavMoveClipDir, g.NavMoveFlags, g.NavMoveScrollFlags);

    // Moving with no reference triggers an init request (will be used as a fallback if the direction fails to find a match)
    if (g.NavMoveSubmitted && g.NavId == 0)
    {
        IMGUI_DEBUG_LOG_NAV("[nav] NavInitRequest: from move, window \"%s\", layer=%d\n", window ? window->Name : "<NULL>", g.NavLayer);
        g.NavInitRequest = g.NavInitRequestFromMove = true;
        g.NavInitResult.ID = 0;
        g.NavDisableHighlight = false;
    }

    // When using gamepad, we project the reference nav bounding box into window visible area.
    // This is to allow resuming navigation inside the visible area after doing a large amount of scrolling,
    // since with gamepad all movements are relative (can't focus a visible object like we can with the mouse).
    if (g.NavMoveSubmitted && g.NavInputSource == ImGuiInputSource_Gamepad && g.NavLayer == ImGuiNavLayer_Main && window != NULL)// && (g.NavMoveFlags & ImGuiNavMoveFlags_Forwarded))
    {
        bool clamp_x = (g.NavMoveFlags & (ImGuiNavMoveFlags_LoopX | ImGuiNavMoveFlags_WrapX)) == 0;
        bool clamp_y = (g.NavMoveFlags & (ImGuiNavMoveFlags_LoopY | ImGuiNavMoveFlags_WrapY)) == 0;
        ImRect inner_rect_rel = WindowRectAbsToRel(window, ImRect(window->InnerRect.Min - ImVec2(1, 1), window->InnerRect.Max + ImVec2(1, 1)));

        // Take account of changing scroll to handle triggering a new move request on a scrolling frame. (#6171)
        // Otherwise 'inner_rect_rel' would be off on the move result frame.
        inner_rect_rel.Translate(CalcNextScrollFromScrollTargetAndClamp(window) - window->Scroll);

        if ((clamp_x || clamp_y) && !inner_rect_rel.Contains(window->NavRectRel[g.NavLayer]))
        {
            IMGUI_DEBUG_LOG_NAV("[nav] NavMoveRequest: clamp NavRectRel for gamepad move\n");
            float pad_x = ImMin(inner_rect_rel.GetWidth(), window->CalcFontSize() * 0.5f);
            float pad_y = ImMin(inner_rect_rel.GetHeight(), window->CalcFontSize() * 0.5f); // Terrible approximation for the intent of starting navigation from first fully visible item
            inner_rect_rel.Min.x = clamp_x ? (inner_rect_rel.Min.x + pad_x) : -FLT_MAX;
            inner_rect_rel.Max.x = clamp_x ? (inner_rect_rel.Max.x - pad_x) : +FLT_MAX;
            inner_rect_rel.Min.y = clamp_y ? (inner_rect_rel.Min.y + pad_y) : -FLT_MAX;
            inner_rect_rel.Max.y = clamp_y ? (inner_rect_rel.Max.y - pad_y) : +FLT_MAX;
            window->NavRectRel[g.NavLayer].ClipWithFull(inner_rect_rel);
            g.NavId = 0;
        }
    }

    // For scoring we use a single segment on the left side our current item bounding box (not touching the edge to avoid box overlap with zero-spaced items)
    ImRect scoring_rect;
    if (window != NULL)
    {
        ImRect nav_rect_rel = !window->NavRectRel[g.NavLayer].IsInverted() ? window->NavRectRel[g.NavLayer] : ImRect(0, 0, 0, 0);
        scoring_rect = WindowRectRelToAbs(window, nav_rect_rel);
        scoring_rect.TranslateY(scoring_rect_offset_y);
        if (g.NavMoveSubmitted)
            NavBiasScoringRect(scoring_rect, window->RootWindowForNav->NavPreferredScoringPosRel[g.NavLayer], g.NavMoveDir, g.NavMoveFlags);
        IM_ASSERT(!scoring_rect.IsInverted()); // Ensure we have a non-inverted bounding box here will allow us to remove extraneous ImFabs() calls in NavScoreItem().
        //GetForegroundDrawList()->AddRect(scoring_rect.Min, scoring_rect.Max, IM_COL32(255,200,0,255)); // [DEBUG]
        //if (!g.NavScoringNoClipRect.IsInverted()) { GetForegroundDrawList()->AddRect(g.NavScoringNoClipRect.Min, g.NavScoringNoClipRect.Max, IM_COL32(255, 200, 0, 255)); } // [DEBUG]
    }
    g.NavScoringRect = scoring_rect;
    g.NavScoringNoClipRect.Add(scoring_rect);
}

void ImGui::NavUpdateCreateTabbingRequest()
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.NavWindow;
    IM_ASSERT(g.NavMoveDir == ImGuiDir_None);
    if (window == NULL || g.NavWindowingTarget != NULL || (window->Flags & ImGuiWindowFlags_NoNavInputs))
        return;

    const bool tab_pressed = IsKeyPressed(ImGuiKey_Tab, ImGuiKeyOwner_None, ImGuiInputFlags_Repeat) && !g.IO.KeyCtrl && !g.IO.KeyAlt;
    if (!tab_pressed)
        return;

    // Initiate tabbing request
    // (this is ALWAYS ENABLED, regardless of ImGuiConfigFlags_NavEnableKeyboard flag!)
    // See NavProcessItemForTabbingRequest() for a description of the various forward/backward tabbing cases with and without wrapping.
    const bool nav_keyboard_active = (g.IO.ConfigFlags & ImGuiConfigFlags_NavEnableKeyboard) != 0;
    if (nav_keyboard_active)
        g.NavTabbingDir = g.IO.KeyShift ? -1 : (g.NavDisableHighlight == true && g.ActiveId == 0) ? 0 : +1;
    else
        g.NavTabbingDir = g.IO.KeyShift ? -1 : (g.ActiveId == 0) ? 0 : +1;
    ImGuiNavMoveFlags move_flags = ImGuiNavMoveFlags_IsTabbing | ImGuiNavMoveFlags_Activate;
    ImGuiScrollFlags scroll_flags = window->Appearing ? ImGuiScrollFlags_KeepVisibleEdgeX | ImGuiScrollFlags_AlwaysCenterY : ImGuiScrollFlags_KeepVisibleEdgeX | ImGuiScrollFlags_KeepVisibleEdgeY;
    ImGuiDir clip_dir = (g.NavTabbingDir < 0) ? ImGuiDir_Up : ImGuiDir_Down;
    NavMoveRequestSubmit(ImGuiDir_None, clip_dir, move_flags, scroll_flags); // FIXME-NAV: Once we refactor tabbing, add LegacyApi flag to not activate non-inputable.
    g.NavTabbingCounter = -1;
}

// Apply result from previous frame navigation directional move request. Always called from NavUpdate()
void ImGui::NavMoveRequestApplyResult()
{
    ImGuiContext& g = *GImGui;
#if IMGUI_DEBUG_NAV_SCORING
    if (g.NavMoveFlags & ImGuiNavMoveFlags_DebugNoResult) // [DEBUG] Scoring all items in NavWindow at all times
        return;
#endif

    // Select which result to use
    ImGuiNavItemData* result = (g.NavMoveResultLocal.ID != 0) ? &g.NavMoveResultLocal : (g.NavMoveResultOther.ID != 0) ? &g.NavMoveResultOther : NULL;

    // Tabbing forward wrap
    if ((g.NavMoveFlags & ImGuiNavMoveFlags_IsTabbing) && result == NULL)
        if ((g.NavTabbingCounter == 1 || g.NavTabbingDir == 0) && g.NavTabbingResultFirst.ID)
            result = &g.NavTabbingResultFirst;

    // In a situation when there are no results but NavId != 0, re-enable the Navigation highlight (because g.NavId is not considered as a possible result)
    const ImGuiAxis axis = (g.NavMoveDir == ImGuiDir_Up || g.NavMoveDir == ImGuiDir_Down) ? ImGuiAxis_Y : ImGuiAxis_X;
    if (result == NULL)
    {
        if (g.NavMoveFlags & ImGuiNavMoveFlags_IsTabbing)
            g.NavMoveFlags |= ImGuiNavMoveFlags_NoSetNavHighlight;
        if (g.NavId != 0 && (g.NavMoveFlags & ImGuiNavMoveFlags_NoSetNavHighlight) == 0)
            NavRestoreHighlightAfterMove();
        NavClearPreferredPosForAxis(axis); // On a failed move, clear preferred pos for this axis.
        IMGUI_DEBUG_LOG_NAV("[nav] NavMoveSubmitted but not led to a result!\n");
        return;
    }

    // PageUp/PageDown behavior first jumps to the bottom/top mostly visible item, _otherwise_ use the result from the previous/next page.
    if (g.NavMoveFlags & ImGuiNavMoveFlags_AlsoScoreVisibleSet)
        if (g.NavMoveResultLocalVisible.ID != 0 && g.NavMoveResultLocalVisible.ID != g.NavId)
            result = &g.NavMoveResultLocalVisible;

    // Maybe entering a flattened child from the outside? In this case solve the tie using the regular scoring rules.
    if (result != &g.NavMoveResultOther && g.NavMoveResultOther.ID != 0 && g.NavMoveResultOther.Window->ParentWindow == g.NavWindow)
        if ((g.NavMoveResultOther.DistBox < result->DistBox) || (g.NavMoveResultOther.DistBox == result->DistBox && g.NavMoveResultOther.DistCenter < result->DistCenter))
            result = &g.NavMoveResultOther;
    IM_ASSERT(g.NavWindow && result->Window);

    // Scroll to keep newly navigated item fully into view.
    if (g.NavLayer == ImGuiNavLayer_Main)
    {
        ImRect rect_abs = WindowRectRelToAbs(result->Window, result->RectRel);
        ScrollToRectEx(result->Window, rect_abs, g.NavMoveScrollFlags);

        if (g.NavMoveFlags & ImGuiNavMoveFlags_ScrollToEdgeY)
        {
            // FIXME: Should remove this? Or make more precise: use ScrollToRectEx() with edge?
            float scroll_target = (g.NavMoveDir == ImGuiDir_Up) ? result->Window->ScrollMax.y : 0.0f;
            SetScrollY(result->Window, scroll_target);
        }
    }

    if (g.NavWindow != result->Window)
    {
        IMGUI_DEBUG_LOG_FOCUS("[focus] NavMoveRequest: SetNavWindow(\"%s\")\n", result->Window->Name);
        g.NavWindow = result->Window;
        g.NavLastValidSelectionUserData = ImGuiSelectionUserData_Invalid;
    }
    if (g.ActiveId != result->ID)
        ClearActiveID();

    // Don't set NavJustMovedToId if just landed on the same spot (which may happen with ImGuiNavMoveFlags_AllowCurrentNavId)
    // PageUp/PageDown however sets always set NavJustMovedTo (vs Home/End which doesn't) mimicking Windows behavior.
    if ((g.NavId != result->ID || (g.NavMoveFlags & ImGuiNavMoveFlags_IsPageMove)) && (g.NavMoveFlags & ImGuiNavMoveFlags_NoSelect) == 0)
    {
        g.NavJustMovedToId = result->ID;
        g.NavJustMovedToFocusScopeId = result->FocusScopeId;
        g.NavJustMovedToKeyMods = g.NavMoveKeyMods;
    }

    // Apply new NavID/Focus
    IMGUI_DEBUG_LOG_NAV("[nav] NavMoveRequest: result NavID 0x%08X in Layer %d Window \"%s\"\n", result->ID, g.NavLayer, g.NavWindow->Name);
    ImVec2 preferred_scoring_pos_rel = g.NavWindow->RootWindowForNav->NavPreferredScoringPosRel[g.NavLayer];
    SetNavID(result->ID, g.NavLayer, result->FocusScopeId, result->RectRel);
    if (result->SelectionUserData != ImGuiSelectionUserData_Invalid)
        g.NavLastValidSelectionUserData = result->SelectionUserData;

    // Restore last preferred position for current axis
    // (storing in RootWindowForNav-> as the info is desirable at the beginning of a Move Request. In theory all storage should use RootWindowForNav..)
    if ((g.NavMoveFlags & ImGuiNavMoveFlags_IsTabbing) == 0)
    {
        preferred_scoring_pos_rel[axis] = result->RectRel.GetCenter()[axis];
        g.NavWindow->RootWindowForNav->NavPreferredScoringPosRel[g.NavLayer] = preferred_scoring_pos_rel;
    }

    // Tabbing: Activates Inputable, otherwise only Focus
    if ((g.NavMoveFlags & ImGuiNavMoveFlags_IsTabbing) && (result->InFlags & ImGuiItemFlags_Inputable) == 0)
        g.NavMoveFlags &= ~ImGuiNavMoveFlags_Activate;

    // Activate
    if (g.NavMoveFlags & ImGuiNavMoveFlags_Activate)
    {
        g.NavNextActivateId = result->ID;
        g.NavNextActivateFlags = ImGuiActivateFlags_None;
        if (g.NavMoveFlags & ImGuiNavMoveFlags_IsTabbing)
            g.NavNextActivateFlags |= ImGuiActivateFlags_PreferInput | ImGuiActivateFlags_TryToPreserveState;
    }

    // Enable nav highlight
    if ((g.NavMoveFlags & ImGuiNavMoveFlags_NoSetNavHighlight) == 0)
        NavRestoreHighlightAfterMove();
}

// Process NavCancel input (to close a popup, get back to parent, clear focus)
// FIXME: In order to support e.g. Escape to clear a selection we'll need:
// - either to store the equivalent of ActiveIdUsingKeyInputMask for a FocusScope and test for it.
// - either to move most/all of those tests to the epilogue/end functions of the scope they are dealing with (e.g. exit child window in EndChild()) or in EndFrame(), to allow an earlier intercept
static void ImGui::NavUpdateCancelRequest()
{
    ImGuiContext& g = *GImGui;
    const bool nav_gamepad_active = (g.IO.ConfigFlags & ImGuiConfigFlags_NavEnableGamepad) != 0 && (g.IO.BackendFlags & ImGuiBackendFlags_HasGamepad) != 0;
    const bool nav_keyboard_active = (g.IO.ConfigFlags & ImGuiConfigFlags_NavEnableKeyboard) != 0;
    if (!(nav_keyboard_active && IsKeyPressed(ImGuiKey_Escape, ImGuiKeyOwner_None)) && !(nav_gamepad_active && IsKeyPressed(ImGuiKey_NavGamepadCancel, ImGuiKeyOwner_None)))
        return;

    IMGUI_DEBUG_LOG_NAV("[nav] NavUpdateCancelRequest()\n");
    if (g.ActiveId != 0)
    {
        ClearActiveID();
    }
    else if (g.NavLayer != ImGuiNavLayer_Main)
    {
        // Leave the "menu" layer
        NavRestoreLayer(ImGuiNavLayer_Main);
        NavRestoreHighlightAfterMove();
    }
    else if (g.NavWindow && g.NavWindow != g.NavWindow->RootWindow && !(g.NavWindow->Flags & ImGuiWindowFlags_Popup) && g.NavWindow->ParentWindow)
    {
        // Exit child window
        ImGuiWindow* child_window = g.NavWindow;
        ImGuiWindow* parent_window = g.NavWindow->ParentWindow;
        IM_ASSERT(child_window->ChildId != 0);
        ImRect child_rect = child_window->Rect();
        FocusWindow(parent_window);
        SetNavID(child_window->ChildId, ImGuiNavLayer_Main, 0, WindowRectAbsToRel(parent_window, child_rect));
        NavRestoreHighlightAfterMove();
    }
    else if (g.OpenPopupStack.Size > 0 && g.OpenPopupStack.back().Window != NULL && !(g.OpenPopupStack.back().Window->Flags & ImGuiWindowFlags_Modal))
    {
        // Close open popup/menu
        ClosePopupToLevel(g.OpenPopupStack.Size - 1, true);
    }
    else
    {
        // Clear NavLastId for popups but keep it for regular child window so we can leave one and come back where we were
        if (g.NavWindow && ((g.NavWindow->Flags & ImGuiWindowFlags_Popup) || !(g.NavWindow->Flags & ImGuiWindowFlags_ChildWindow)))
            g.NavWindow->NavLastIds[0] = 0;
        g.NavId = 0;
    }
}

// Handle PageUp/PageDown/Home/End keys
// Called from NavUpdateCreateMoveRequest() which will use our output to create a move request
// FIXME-NAV: This doesn't work properly with NavFlattened siblings as we use NavWindow rectangle for reference
// FIXME-NAV: how to get Home/End to aim at the beginning/end of a 2D grid?
static float ImGui::NavUpdatePageUpPageDown()
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.NavWindow;
    if ((window->Flags & ImGuiWindowFlags_NoNavInputs) || g.NavWindowingTarget != NULL)
        return 0.0f;

    const bool page_up_held = IsKeyDown(ImGuiKey_PageUp, ImGuiKeyOwner_None);
    const bool page_down_held = IsKeyDown(ImGuiKey_PageDown, ImGuiKeyOwner_None);
    const bool home_pressed = IsKeyPressed(ImGuiKey_Home, ImGuiKeyOwner_None, ImGuiInputFlags_Repeat);
    const bool end_pressed = IsKeyPressed(ImGuiKey_End, ImGuiKeyOwner_None, ImGuiInputFlags_Repeat);
    if (page_up_held == page_down_held && home_pressed == end_pressed) // Proceed if either (not both) are pressed, otherwise early out
        return 0.0f;

    if (g.NavLayer != ImGuiNavLayer_Main)
        NavRestoreLayer(ImGuiNavLayer_Main);

    if (window->DC.NavLayersActiveMask == 0x00 && window->DC.NavWindowHasScrollY)
    {
        // Fallback manual-scroll when window has no navigable item
        if (IsKeyPressed(ImGuiKey_PageUp, ImGuiKeyOwner_None, ImGuiInputFlags_Repeat))
            SetScrollY(window, window->Scroll.y - window->InnerRect.GetHeight());
        else if (IsKeyPressed(ImGuiKey_PageDown, ImGuiKeyOwner_None, ImGuiInputFlags_Repeat))
            SetScrollY(window, window->Scroll.y + window->InnerRect.GetHeight());
        else if (home_pressed)
            SetScrollY(window, 0.0f);
        else if (end_pressed)
            SetScrollY(window, window->ScrollMax.y);
    }
    else
    {
        ImRect& nav_rect_rel = window->NavRectRel[g.NavLayer];
        const float page_offset_y = ImMax(0.0f, window->InnerRect.GetHeight() - window->CalcFontSize() * 1.0f + nav_rect_rel.GetHeight());
        float nav_scoring_rect_offset_y = 0.0f;
        if (IsKeyPressed(ImGuiKey_PageUp, true))
        {
            nav_scoring_rect_offset_y = -page_offset_y;
            g.NavMoveDir = ImGuiDir_Down; // Because our scoring rect is offset up, we request the down direction (so we can always land on the last item)
            g.NavMoveClipDir = ImGuiDir_Up;
            g.NavMoveFlags = ImGuiNavMoveFlags_AllowCurrentNavId | ImGuiNavMoveFlags_AlsoScoreVisibleSet | ImGuiNavMoveFlags_IsPageMove;
        }
        else if (IsKeyPressed(ImGuiKey_PageDown, true))
        {
            nav_scoring_rect_offset_y = +page_offset_y;
            g.NavMoveDir = ImGuiDir_Up; // Because our scoring rect is offset down, we request the up direction (so we can always land on the last item)
            g.NavMoveClipDir = ImGuiDir_Down;
            g.NavMoveFlags = ImGuiNavMoveFlags_AllowCurrentNavId | ImGuiNavMoveFlags_AlsoScoreVisibleSet | ImGuiNavMoveFlags_IsPageMove;
        }
        else if (home_pressed)
        {
            // FIXME-NAV: handling of Home/End is assuming that the top/bottom most item will be visible with Scroll.y == 0/ScrollMax.y
            // Scrolling will be handled via the ImGuiNavMoveFlags_ScrollToEdgeY flag, we don't scroll immediately to avoid scrolling happening before nav result.
            // Preserve current horizontal position if we have any.
            nav_rect_rel.Min.y = nav_rect_rel.Max.y = 0.0f;
            if (nav_rect_rel.IsInverted())
                nav_rect_rel.Min.x = nav_rect_rel.Max.x = 0.0f;
            g.NavMoveDir = ImGuiDir_Down;
            g.NavMoveFlags = ImGuiNavMoveFlags_AllowCurrentNavId | ImGuiNavMoveFlags_ScrollToEdgeY;
            // FIXME-NAV: MoveClipDir left to _None, intentional?
        }
        else if (end_pressed)
        {
            nav_rect_rel.Min.y = nav_rect_rel.Max.y = window->ContentSize.y;
            if (nav_rect_rel.IsInverted())
                nav_rect_rel.Min.x = nav_rect_rel.Max.x = 0.0f;
            g.NavMoveDir = ImGuiDir_Up;
            g.NavMoveFlags = ImGuiNavMoveFlags_AllowCurrentNavId | ImGuiNavMoveFlags_ScrollToEdgeY;
            // FIXME-NAV: MoveClipDir left to _None, intentional?
        }
        return nav_scoring_rect_offset_y;
    }
    return 0.0f;
}

static void ImGui::NavEndFrame()
{
    ImGuiContext& g = *GImGui;

    // Show CTRL+TAB list window
    if (g.NavWindowingTarget != NULL)
        NavUpdateWindowingOverlay();

    // Perform wrap-around in menus
    // FIXME-NAV: Wrap may need to apply a weight bias on the other axis. e.g. 4x4 grid with 2 last items missing on last item won't handle LoopY/WrapY correctly.
    // FIXME-NAV: Wrap (not Loop) support could be handled by the scoring function and then WrapX would function without an extra frame.
    if (g.NavWindow && NavMoveRequestButNoResultYet() && (g.NavMoveFlags & ImGuiNavMoveFlags_WrapMask_) && (g.NavMoveFlags & ImGuiNavMoveFlags_Forwarded) == 0)
        NavUpdateCreateWrappingRequest();
}

static void ImGui::NavUpdateCreateWrappingRequest()
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.NavWindow;

    bool do_forward = false;
    ImRect bb_rel = window->NavRectRel[g.NavLayer];
    ImGuiDir clip_dir = g.NavMoveDir;

    const ImGuiNavMoveFlags move_flags = g.NavMoveFlags;
    //const ImGuiAxis move_axis = (g.NavMoveDir == ImGuiDir_Up || g.NavMoveDir == ImGuiDir_Down) ? ImGuiAxis_Y : ImGuiAxis_X;
    if (g.NavMoveDir == ImGuiDir_Left && (move_flags & (ImGuiNavMoveFlags_WrapX | ImGuiNavMoveFlags_LoopX)))
    {
        bb_rel.Min.x = bb_rel.Max.x = window->ContentSize.x + window->WindowPadding.x;
        if (move_flags & ImGuiNavMoveFlags_WrapX)
        {
            bb_rel.TranslateY(-bb_rel.GetHeight()); // Previous row
            clip_dir = ImGuiDir_Up;
        }
        do_forward = true;
    }
    if (g.NavMoveDir == ImGuiDir_Right && (move_flags & (ImGuiNavMoveFlags_WrapX | ImGuiNavMoveFlags_LoopX)))
    {
        bb_rel.Min.x = bb_rel.Max.x = -window->WindowPadding.x;
        if (move_flags & ImGuiNavMoveFlags_WrapX)
        {
            bb_rel.TranslateY(+bb_rel.GetHeight()); // Next row
            clip_dir = ImGuiDir_Down;
        }
        do_forward = true;
    }
    if (g.NavMoveDir == ImGuiDir_Up && (move_flags & (ImGuiNavMoveFlags_WrapY | ImGuiNavMoveFlags_LoopY)))
    {
        bb_rel.Min.y = bb_rel.Max.y = window->ContentSize.y + window->WindowPadding.y;
        if (move_flags & ImGuiNavMoveFlags_WrapY)
        {
            bb_rel.TranslateX(-bb_rel.GetWidth()); // Previous column
            clip_dir = ImGuiDir_Left;
        }
        do_forward = true;
    }
    if (g.NavMoveDir == ImGuiDir_Down && (move_flags & (ImGuiNavMoveFlags_WrapY | ImGuiNavMoveFlags_LoopY)))
    {
        bb_rel.Min.y = bb_rel.Max.y = -window->WindowPadding.y;
        if (move_flags & ImGuiNavMoveFlags_WrapY)
        {
            bb_rel.TranslateX(+bb_rel.GetWidth()); // Next column
            clip_dir = ImGuiDir_Right;
        }
        do_forward = true;
    }
    if (!do_forward)
        return;
    window->NavRectRel[g.NavLayer] = bb_rel;
    NavClearPreferredPosForAxis(ImGuiAxis_X);
    NavClearPreferredPosForAxis(ImGuiAxis_Y);
    NavMoveRequestForward(g.NavMoveDir, clip_dir, move_flags, g.NavMoveScrollFlags);
}

static int ImGui::FindWindowFocusIndex(ImGuiWindow* window)
{
    ImGuiContext& g = *GImGui;
    IM_UNUSED(g);
    int order = window->FocusOrder;
    IM_ASSERT(window->RootWindow == window); // No child window (not testing _ChildWindow because of docking)
    IM_ASSERT(g.WindowsFocusOrder[order] == window);
    return order;
}

static ImGuiWindow* FindWindowNavFocusable(int i_start, int i_stop, int dir) // FIXME-OPT O(N)
{
    ImGuiContext& g = *GImGui;
    for (int i = i_start; i >= 0 && i < g.WindowsFocusOrder.Size && i != i_stop; i += dir)
        if (ImGui::IsWindowNavFocusable(g.WindowsFocusOrder[i]))
            return g.WindowsFocusOrder[i];
    return NULL;
}

static void NavUpdateWindowingHighlightWindow(int focus_change_dir)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(g.NavWindowingTarget);
    if (g.NavWindowingTarget->Flags & ImGuiWindowFlags_Modal)
        return;

    const int i_current = ImGui::FindWindowFocusIndex(g.NavWindowingTarget);
    ImGuiWindow* window_target = FindWindowNavFocusable(i_current + focus_change_dir, -INT_MAX, focus_change_dir);
    if (!window_target)
        window_target = FindWindowNavFocusable((focus_change_dir < 0) ? (g.WindowsFocusOrder.Size - 1) : 0, i_current, focus_change_dir);
    if (window_target) // Don't reset windowing target if there's a single window in the list
    {
        g.NavWindowingTarget = g.NavWindowingTargetAnim = window_target;
        g.NavWindowingAccumDeltaPos = g.NavWindowingAccumDeltaSize = ImVec2(0.0f, 0.0f);
    }
    g.NavWindowingToggleLayer = false;
}

// Windowing management mode
// Keyboard: CTRL+Tab (change focus/move/resize), Alt (toggle menu layer)
// Gamepad:  Hold Menu/Square (change focus/move/resize), Tap Menu/Square (toggle menu layer)
static void ImGui::NavUpdateWindowing()
{
    ImGuiContext& g = *GImGui;
    ImGuiIO& io = g.IO;

    ImGuiWindow* apply_focus_window = NULL;
    bool apply_toggle_layer = false;

    ImGuiWindow* modal_window = GetTopMostPopupModal();
    bool allow_windowing = (modal_window == NULL); // FIXME: This prevent CTRL+TAB from being usable with windows that are inside the Begin-stack of that modal.
    if (!allow_windowing)
        g.NavWindowingTarget = NULL;

    // Fade out
    if (g.NavWindowingTargetAnim && g.NavWindowingTarget == NULL)
    {
        g.NavWindowingHighlightAlpha = ImMax(g.NavWindowingHighlightAlpha - io.DeltaTime * 10.0f, 0.0f);
        if (g.DimBgRatio <= 0.0f && g.NavWindowingHighlightAlpha <= 0.0f)
            g.NavWindowingTargetAnim = NULL;
    }

    // Start CTRL+Tab or Square+L/R window selection
    const ImGuiID owner_id = ImHashStr("###NavUpdateWindowing");
    const bool nav_gamepad_active = (io.ConfigFlags & ImGuiConfigFlags_NavEnableGamepad) != 0 && (io.BackendFlags & ImGuiBackendFlags_HasGamepad) != 0;
    const bool nav_keyboard_active = (io.ConfigFlags & ImGuiConfigFlags_NavEnableKeyboard) != 0;
    const bool keyboard_next_window = allow_windowing && g.ConfigNavWindowingKeyNext && Shortcut(g.ConfigNavWindowingKeyNext, owner_id, ImGuiInputFlags_Repeat | ImGuiInputFlags_RouteAlways);
    const bool keyboard_prev_window = allow_windowing && g.ConfigNavWindowingKeyPrev && Shortcut(g.ConfigNavWindowingKeyPrev, owner_id, ImGuiInputFlags_Repeat | ImGuiInputFlags_RouteAlways);
    const bool start_windowing_with_gamepad = allow_windowing && nav_gamepad_active && !g.NavWindowingTarget && IsKeyPressed(ImGuiKey_NavGamepadMenu, 0, ImGuiInputFlags_None);
    const bool start_windowing_with_keyboard = allow_windowing && !g.NavWindowingTarget && (keyboard_next_window || keyboard_prev_window); // Note: enabled even without NavEnableKeyboard!
    if (start_windowing_with_gamepad || start_windowing_with_keyboard)
        if (ImGuiWindow* window = g.NavWindow ? g.NavWindow : FindWindowNavFocusable(g.WindowsFocusOrder.Size - 1, -INT_MAX, -1))
        {
            g.NavWindowingTarget = g.NavWindowingTargetAnim = window->RootWindow;
            g.NavWindowingTimer = g.NavWindowingHighlightAlpha = 0.0f;
            g.NavWindowingAccumDeltaPos = g.NavWindowingAccumDeltaSize = ImVec2(0.0f, 0.0f);
            g.NavWindowingToggleLayer = start_windowing_with_gamepad ? true : false; // Gamepad starts toggling layer
            g.NavInputSource = start_windowing_with_keyboard ? ImGuiInputSource_Keyboard : ImGuiInputSource_Gamepad;

            // Register ownership of our mods. Using ImGuiInputFlags_RouteGlobalHigh in the Shortcut() calls instead would probably be correct but may have more side-effects.
            if (keyboard_next_window || keyboard_prev_window)
                SetKeyOwnersForKeyChord((g.ConfigNavWindowingKeyNext | g.ConfigNavWindowingKeyPrev) & ImGuiMod_Mask_, owner_id);
        }

    // Gamepad update
    g.NavWindowingTimer += io.DeltaTime;
    if (g.NavWindowingTarget && g.NavInputSource == ImGuiInputSource_Gamepad)
    {
        // Highlight only appears after a brief time holding the button, so that a fast tap on PadMenu (to toggle NavLayer) doesn't add visual noise
        g.NavWindowingHighlightAlpha = ImMax(g.NavWindowingHighlightAlpha, ImSaturate((g.NavWindowingTimer - NAV_WINDOWING_HIGHLIGHT_DELAY) / 0.05f));

        // Select window to focus
        const int focus_change_dir = (int)IsKeyPressed(ImGuiKey_GamepadL1) - (int)IsKeyPressed(ImGuiKey_GamepadR1);
        if (focus_change_dir != 0)
        {
            NavUpdateWindowingHighlightWindow(focus_change_dir);
            g.NavWindowingHighlightAlpha = 1.0f;
        }

        // Single press toggles NavLayer, long press with L/R apply actual focus on release (until then the window was merely rendered top-most)
        if (!IsKeyDown(ImGuiKey_NavGamepadMenu))
        {
            g.NavWindowingToggleLayer &= (g.NavWindowingHighlightAlpha < 1.0f); // Once button was held long enough we don't consider it a tap-to-toggle-layer press anymore.
            if (g.NavWindowingToggleLayer && g.NavWindow)
                apply_toggle_layer = true;
            else if (!g.NavWindowingToggleLayer)
                apply_focus_window = g.NavWindowingTarget;
            g.NavWindowingTarget = NULL;
        }
    }

    // Keyboard: Focus
    if (g.NavWindowingTarget && g.NavInputSource == ImGuiInputSource_Keyboard)
    {
        // Visuals only appears after a brief time after pressing TAB the first time, so that a fast CTRL+TAB doesn't add visual noise
        ImGuiKeyChord shared_mods = ((g.ConfigNavWindowingKeyNext ? g.ConfigNavWindowingKeyNext : ImGuiMod_Mask_) & (g.ConfigNavWindowingKeyPrev ? g.ConfigNavWindowingKeyPrev : ImGuiMod_Mask_)) & ImGuiMod_Mask_;
        IM_ASSERT(shared_mods != 0); // Next/Prev shortcut currently needs a shared modifier to "hold", otherwise Prev actions would keep cycling between two windows.
        g.NavWindowingHighlightAlpha = ImMax(g.NavWindowingHighlightAlpha, ImSaturate((g.NavWindowingTimer - NAV_WINDOWING_HIGHLIGHT_DELAY) / 0.05f)); // 1.0f
        if (keyboard_next_window || keyboard_prev_window)
            NavUpdateWindowingHighlightWindow(keyboard_next_window ? -1 : +1);
        else if ((io.KeyMods & shared_mods) != shared_mods)
            apply_focus_window = g.NavWindowingTarget;
    }

    // Keyboard: Press and Release ALT to toggle menu layer
    // - Testing that only Alt is tested prevents Alt+Shift or AltGR from toggling menu layer.
    // - AltGR is normally Alt+Ctrl but we can't reliably detect it (not all backends/systems/layout emit it as Alt+Ctrl). But even on keyboards without AltGR we don't want Alt+Ctrl to open menu anyway.
    if (nav_keyboard_active && IsKeyPressed(ImGuiMod_Alt, ImGuiKeyOwner_None))
    {
        g.NavWindowingToggleLayer = true;
        g.NavInputSource = ImGuiInputSource_Keyboard;
    }
    if (g.NavWindowingToggleLayer && g.NavInputSource == ImGuiInputSource_Keyboard)
    {
        // We cancel toggling nav layer when any text has been typed (generally while holding Alt). (See #370)
        // We cancel toggling nav layer when other modifiers are pressed. (See #4439)
        // We cancel toggling nav layer if an owner has claimed the key.
        if (io.InputQueueCharacters.Size > 0 || io.KeyCtrl || io.KeyShift || io.KeySuper || TestKeyOwner(ImGuiMod_Alt, ImGuiKeyOwner_None) == false)
            g.NavWindowingToggleLayer = false;

        // Apply layer toggle on release
        // Important: as before version <18314 we lacked an explicit IO event for focus gain/loss, we also compare mouse validity to detect old backends clearing mouse pos on focus loss.
        if (IsKeyReleased(ImGuiMod_Alt) && g.NavWindowingToggleLayer)
            if (g.ActiveId == 0 || g.ActiveIdAllowOverlap)
                if (IsMousePosValid(&io.MousePos) == IsMousePosValid(&io.MousePosPrev))
                    apply_toggle_layer = true;
        if (!IsKeyDown(ImGuiMod_Alt))
            g.NavWindowingToggleLayer = false;
    }

    // Move window
    if (g.NavWindowingTarget && !(g.NavWindowingTarget->Flags & ImGuiWindowFlags_NoMove))
    {
        ImVec2 nav_move_dir;
        if (g.NavInputSource == ImGuiInputSource_Keyboard && !io.KeyShift)
            nav_move_dir = GetKeyMagnitude2d(ImGuiKey_LeftArrow, ImGuiKey_RightArrow, ImGuiKey_UpArrow, ImGuiKey_DownArrow);
        if (g.NavInputSource == ImGuiInputSource_Gamepad)
            nav_move_dir = GetKeyMagnitude2d(ImGuiKey_GamepadLStickLeft, ImGuiKey_GamepadLStickRight, ImGuiKey_GamepadLStickUp, ImGuiKey_GamepadLStickDown);
        if (nav_move_dir.x != 0.0f || nav_move_dir.y != 0.0f)
        {
            const float NAV_MOVE_SPEED = 800.0f;
            const float move_step = NAV_MOVE_SPEED * io.DeltaTime * ImMin(io.DisplayFramebufferScale.x, io.DisplayFramebufferScale.y);
            g.NavWindowingAccumDeltaPos += nav_move_dir * move_step;
            g.NavDisableMouseHover = true;
            ImVec2 accum_floored = ImTrunc(g.NavWindowingAccumDeltaPos);
            if (accum_floored.x != 0.0f || accum_floored.y != 0.0f)
            {
                ImGuiWindow* moving_window = g.NavWindowingTarget->RootWindowDockTree;
                SetWindowPos(moving_window, moving_window->Pos + accum_floored, ImGuiCond_Always);
                g.NavWindowingAccumDeltaPos -= accum_floored;
            }
        }
    }

    // Apply final focus
    if (apply_focus_window && (g.NavWindow == NULL || apply_focus_window != g.NavWindow->RootWindow))
    {
        // FIXME: Many actions here could be part of a higher-level/reused function. Why aren't they in FocusWindow()
        // Investigate for each of them: ClearActiveID(), NavRestoreHighlightAfterMove(), NavRestoreLastChildNavWindow(), ClosePopupsOverWindow(), NavInitWindow()
        ImGuiViewport* previous_viewport = g.NavWindow ? g.NavWindow->Viewport : NULL;
        ClearActiveID();
        NavRestoreHighlightAfterMove();
        ClosePopupsOverWindow(apply_focus_window, false);
        FocusWindow(apply_focus_window, ImGuiFocusRequestFlags_RestoreFocusedChild);
        apply_focus_window = g.NavWindow;
        if (apply_focus_window->NavLastIds[0] == 0)
            NavInitWindow(apply_focus_window, false);

        // If the window has ONLY a menu layer (no main layer), select it directly
        // Use NavLayersActiveMaskNext since windows didn't have a chance to be Begin()-ed on this frame,
        // so CTRL+Tab where the keys are only held for 1 frame will be able to use correct layers mask since
        // the target window as already been previewed once.
        // FIXME-NAV: This should be done in NavInit.. or in FocusWindow... However in both of those cases,
        // we won't have a guarantee that windows has been visible before and therefore NavLayersActiveMask*
        // won't be valid.
        if (apply_focus_window->DC.NavLayersActiveMaskNext == (1 << ImGuiNavLayer_Menu))
            g.NavLayer = ImGuiNavLayer_Menu;

        // Request OS level focus
        if (apply_focus_window->Viewport != previous_viewport && g.PlatformIO.Platform_SetWindowFocus)
            g.PlatformIO.Platform_SetWindowFocus(apply_focus_window->Viewport);
    }
    if (apply_focus_window)
        g.NavWindowingTarget = NULL;

    // Apply menu/layer toggle
    if (apply_toggle_layer && g.NavWindow)
    {
        ClearActiveID();

        // Move to parent menu if necessary
        ImGuiWindow* new_nav_window = g.NavWindow;
        while (new_nav_window->ParentWindow
            && (new_nav_window->DC.NavLayersActiveMask & (1 << ImGuiNavLayer_Menu)) == 0
            && (new_nav_window->Flags & ImGuiWindowFlags_ChildWindow) != 0
            && (new_nav_window->Flags & (ImGuiWindowFlags_Popup | ImGuiWindowFlags_ChildMenu)) == 0)
            new_nav_window = new_nav_window->ParentWindow;
        if (new_nav_window != g.NavWindow)
        {
            ImGuiWindow* old_nav_window = g.NavWindow;
            FocusWindow(new_nav_window);
            new_nav_window->NavLastChildNavWindow = old_nav_window;
        }

        // Toggle layer
        const ImGuiNavLayer new_nav_layer = (g.NavWindow->DC.NavLayersActiveMask & (1 << ImGuiNavLayer_Menu)) ? (ImGuiNavLayer)((int)g.NavLayer ^ 1) : ImGuiNavLayer_Main;
        if (new_nav_layer != g.NavLayer)
        {
            // Reinitialize navigation when entering menu bar with the Alt key (FIXME: could be a properly of the layer?)
            const bool preserve_layer_1_nav_id = (new_nav_window->DockNodeAsHost != NULL);
            if (new_nav_layer == ImGuiNavLayer_Menu && !preserve_layer_1_nav_id)
                g.NavWindow->NavLastIds[new_nav_layer] = 0;
            NavRestoreLayer(new_nav_layer);
            NavRestoreHighlightAfterMove();
        }
    }
}

// Window has already passed the IsWindowNavFocusable()
static const char* GetFallbackWindowNameForWindowingList(ImGuiWindow* window)
{
    if (window->Flags & ImGuiWindowFlags_Popup)
        return ImGui::LocalizeGetMsg(ImGuiLocKey_WindowingPopup);
    if ((window->Flags & ImGuiWindowFlags_MenuBar) && strcmp(window->Name, "##MainMenuBar") == 0)
        return ImGui::LocalizeGetMsg(ImGuiLocKey_WindowingMainMenuBar);
    if (window->DockNodeAsHost)
        return "(Dock node)"; // Not normally shown to user.
    return ImGui::LocalizeGetMsg(ImGuiLocKey_WindowingUntitled);
}

// Overlay displayed when using CTRL+TAB. Called by EndFrame().
void ImGui::NavUpdateWindowingOverlay()
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(g.NavWindowingTarget != NULL);

    if (g.NavWindowingTimer < NAV_WINDOWING_LIST_APPEAR_DELAY)
        return;

    if (g.NavWindowingListWindow == NULL)
        g.NavWindowingListWindow = FindWindowByName("###NavWindowingList");
    const ImGuiViewport* viewport = /*g.NavWindow ? g.NavWindow->Viewport :*/ GetMainViewport();
    SetNextWindowSizeConstraints(ImVec2(viewport->Size.x * 0.20f, viewport->Size.y * 0.20f), ImVec2(FLT_MAX, FLT_MAX));
    SetNextWindowPos(viewport->GetCenter(), ImGuiCond_Always, ImVec2(0.5f, 0.5f));
    PushStyleVar(ImGuiStyleVar_WindowPadding, g.Style.WindowPadding * 2.0f);
    Begin("###NavWindowingList", NULL, ImGuiWindowFlags_NoTitleBar | ImGuiWindowFlags_NoFocusOnAppearing | ImGuiWindowFlags_NoResize | ImGuiWindowFlags_NoMove | ImGuiWindowFlags_NoInputs | ImGuiWindowFlags_AlwaysAutoResize | ImGuiWindowFlags_NoSavedSettings);
    for (int n = g.WindowsFocusOrder.Size - 1; n >= 0; n--)
    {
        ImGuiWindow* window = g.WindowsFocusOrder[n];
        IM_ASSERT(window != NULL); // Fix static analyzers
        if (!IsWindowNavFocusable(window))
            continue;
        const char* label = window->Name;
        if (label == FindRenderedTextEnd(label))
            label = GetFallbackWindowNameForWindowingList(window);
        Selectable(label, g.NavWindowingTarget == window);
    }
    End();
    PopStyleVar();
}


//-----------------------------------------------------------------------------
// [SECTION] DRAG AND DROP
//-----------------------------------------------------------------------------

bool ImGui::IsDragDropActive()
{
    ImGuiContext& g = *GImGui;
    return g.DragDropActive;
}

void ImGui::ClearDragDrop()
{
    ImGuiContext& g = *GImGui;
    g.DragDropActive = false;
    g.DragDropPayload.Clear();
    g.DragDropAcceptFlags = ImGuiDragDropFlags_None;
    g.DragDropAcceptIdCurr = g.DragDropAcceptIdPrev = 0;
    g.DragDropAcceptIdCurrRectSurface = FLT_MAX;
    g.DragDropAcceptFrameCount = -1;

    g.DragDropPayloadBufHeap.clear();
    memset(&g.DragDropPayloadBufLocal, 0, sizeof(g.DragDropPayloadBufLocal));
}

bool ImGui::BeginTooltipHidden()
{
    ImGuiContext& g = *GImGui;
    bool ret = Begin("##Tooltip_Hidden", NULL, ImGuiWindowFlags_Tooltip | ImGuiWindowFlags_NoInputs | ImGuiWindowFlags_NoTitleBar | ImGuiWindowFlags_NoMove | ImGuiWindowFlags_NoResize | ImGuiWindowFlags_NoSavedSettings | ImGuiWindowFlags_AlwaysAutoResize);
    SetWindowHiddendAndSkipItemsForCurrentFrame(g.CurrentWindow);
    return ret;
}

// When this returns true you need to: a) call SetDragDropPayload() exactly once, b) you may render the payload visual/description, c) call EndDragDropSource()
// If the item has an identifier:
// - This assume/require the item to be activated (typically via ButtonBehavior).
// - Therefore if you want to use this with a mouse button other than left mouse button, it is up to the item itself to activate with another button.
// - We then pull and use the mouse button that was used to activate the item and use it to carry on the drag.
// If the item has no identifier:
// - Currently always assume left mouse button.
bool ImGui::BeginDragDropSource(ImGuiDragDropFlags flags)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;

    // FIXME-DRAGDROP: While in the common-most "drag from non-zero active id" case we can tell the mouse button,
    // in both SourceExtern and id==0 cases we may requires something else (explicit flags or some heuristic).
    ImGuiMouseButton mouse_button = ImGuiMouseButton_Left;

    bool source_drag_active = false;
    ImGuiID source_id = 0;
    ImGuiID source_parent_id = 0;
    if (!(flags & ImGuiDragDropFlags_SourceExtern))
    {
        source_id = g.LastItemData.ID;
        if (source_id != 0)
        {
            // Common path: items with ID
            if (g.ActiveId != source_id)
                return false;
            if (g.ActiveIdMouseButton != -1)
                mouse_button = g.ActiveIdMouseButton;
            if (g.IO.MouseDown[mouse_button] == false || window->SkipItems)
                return false;
            g.ActiveIdAllowOverlap = false;
        }
        else
        {
            // Uncommon path: items without ID
            if (g.IO.MouseDown[mouse_button] == false || window->SkipItems)
                return false;
            if ((g.LastItemData.StatusFlags & ImGuiItemStatusFlags_HoveredRect) == 0 && (g.ActiveId == 0 || g.ActiveIdWindow != window))
                return false;

            // If you want to use BeginDragDropSource() on an item with no unique identifier for interaction, such as Text() or Image(), you need to:
            // A) Read the explanation below, B) Use the ImGuiDragDropFlags_SourceAllowNullID flag.
            if (!(flags & ImGuiDragDropFlags_SourceAllowNullID))
            {
                IM_ASSERT(0);
                return false;
            }

            // Magic fallback to handle items with no assigned ID, e.g. Text(), Image()
            // We build a throwaway ID based on current ID stack + relative AABB of items in window.
            // THE IDENTIFIER WON'T SURVIVE ANY REPOSITIONING/RESIZINGG OF THE WIDGET, so if your widget moves your dragging operation will be canceled.
            // We don't need to maintain/call ClearActiveID() as releasing the button will early out this function and trigger !ActiveIdIsAlive.
            // Rely on keeping other window->LastItemXXX fields intact.
            source_id = g.LastItemData.ID = window->GetIDFromRectangle(g.LastItemData.Rect);
            KeepAliveID(source_id);
            bool is_hovered = ItemHoverable(g.LastItemData.Rect, source_id, g.LastItemData.InFlags);
            if (is_hovered && g.IO.MouseClicked[mouse_button])
            {
                SetActiveID(source_id, window);
                FocusWindow(window);
            }
            if (g.ActiveId == source_id) // Allow the underlying widget to display/return hovered during the mouse release frame, else we would get a flicker.
                g.ActiveIdAllowOverlap = is_hovered;
        }
        if (g.ActiveId != source_id)
            return false;
        source_parent_id = window->IDStack.back();
        source_drag_active = IsMouseDragging(mouse_button);

        // Disable navigation and key inputs while dragging + cancel existing request if any
        SetActiveIdUsingAllKeyboardKeys();
    }
    else
    {
        window = NULL;
        source_id = ImHashStr("#SourceExtern");
        source_drag_active = true;
    }

    if (source_drag_active)
    {
        if (!g.DragDropActive)
        {
            IM_ASSERT(source_id != 0);
            ClearDragDrop();
            ImGuiPayload& payload = g.DragDropPayload;
            payload.SourceId = source_id;
            payload.SourceParentId = source_parent_id;
            g.DragDropActive = true;
            g.DragDropSourceFlags = flags;
            g.DragDropMouseButton = mouse_button;
            if (payload.SourceId == g.ActiveId)
                g.ActiveIdNoClearOnFocusLoss = true;
        }
        g.DragDropSourceFrameCount = g.FrameCount;
        g.DragDropWithinSource = true;

        if (!(flags & ImGuiDragDropFlags_SourceNoPreviewTooltip))
        {
            // Target can request the Source to not display its tooltip (we use a dedicated flag to make this request explicit)
            // We unfortunately can't just modify the source flags and skip the call to BeginTooltip, as caller may be emitting contents.
            bool ret;
            if (g.DragDropAcceptIdPrev && (g.DragDropAcceptFlags & ImGuiDragDropFlags_AcceptNoPreviewTooltip))
                ret = BeginTooltipHidden();
            else
                ret = BeginTooltip();
            IM_ASSERT(ret); // FIXME-NEWBEGIN: If this ever becomes false, we need to Begin("##Hidden", NULL, ImGuiWindowFlags_NoSavedSettings) + SetWindowHiddendAndSkipItemsForCurrentFrame().
            IM_UNUSED(ret);
        }

        if (!(flags & ImGuiDragDropFlags_SourceNoDisableHover) && !(flags & ImGuiDragDropFlags_SourceExtern))
            g.LastItemData.StatusFlags &= ~ImGuiItemStatusFlags_HoveredRect;

        return true;
    }
    return false;
}

void ImGui::EndDragDropSource()
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(g.DragDropActive);
    IM_ASSERT(g.DragDropWithinSource && "Not after a BeginDragDropSource()?");

    if (!(g.DragDropSourceFlags & ImGuiDragDropFlags_SourceNoPreviewTooltip))
        EndTooltip();

    // Discard the drag if have not called SetDragDropPayload()
    if (g.DragDropPayload.DataFrameCount == -1)
        ClearDragDrop();
    g.DragDropWithinSource = false;
}

// Use 'cond' to choose to submit payload on drag start or every frame
bool ImGui::SetDragDropPayload(const char* type, const void* data, size_t data_size, ImGuiCond cond)
{
    ImGuiContext& g = *GImGui;
    ImGuiPayload& payload = g.DragDropPayload;
    if (cond == 0)
        cond = ImGuiCond_Always;

    IM_ASSERT(type != NULL);
    IM_ASSERT(strlen(type) < IM_ARRAYSIZE(payload.DataType) && "Payload type can be at most 32 characters long");
    IM_ASSERT((data != NULL && data_size > 0) || (data == NULL && data_size == 0));
    IM_ASSERT(cond == ImGuiCond_Always || cond == ImGuiCond_Once);
    IM_ASSERT(payload.SourceId != 0);                               // Not called between BeginDragDropSource() and EndDragDropSource()

    if (cond == ImGuiCond_Always || payload.DataFrameCount == -1)
    {
        // Copy payload
        ImStrncpy(payload.DataType, type, IM_ARRAYSIZE(payload.DataType));
        g.DragDropPayloadBufHeap.resize(0);
        if (data_size > sizeof(g.DragDropPayloadBufLocal))
        {
            // Store in heap
            g.DragDropPayloadBufHeap.resize((int)data_size);
            payload.Data = g.DragDropPayloadBufHeap.Data;
            memcpy(payload.Data, data, data_size);
        }
        else if (data_size > 0)
        {
            // Store locally
            memset(&g.DragDropPayloadBufLocal, 0, sizeof(g.DragDropPayloadBufLocal));
            payload.Data = g.DragDropPayloadBufLocal;
            memcpy(payload.Data, data, data_size);
        }
        else
        {
            payload.Data = NULL;
        }
        payload.DataSize = (int)data_size;
    }
    payload.DataFrameCount = g.FrameCount;

    // Return whether the payload has been accepted
    return (g.DragDropAcceptFrameCount == g.FrameCount) || (g.DragDropAcceptFrameCount == g.FrameCount - 1);
}

bool ImGui::BeginDragDropTargetCustom(const ImRect& bb, ImGuiID id)
{
    ImGuiContext& g = *GImGui;
    if (!g.DragDropActive)
        return false;

    ImGuiWindow* window = g.CurrentWindow;
    ImGuiWindow* hovered_window = g.HoveredWindowUnderMovingWindow;
    if (hovered_window == NULL || window->RootWindowDockTree != hovered_window->RootWindowDockTree)
        return false;
    IM_ASSERT(id != 0);
    if (!IsMouseHoveringRect(bb.Min, bb.Max) || (id == g.DragDropPayload.SourceId))
        return false;
    if (window->SkipItems)
        return false;

    IM_ASSERT(g.DragDropWithinTarget == false);
    g.DragDropTargetRect = bb;
    g.DragDropTargetId = id;
    g.DragDropWithinTarget = true;
    return true;
}

// We don't use BeginDragDropTargetCustom() and duplicate its code because:
// 1) we use LastItemRectHoveredRect which handles items that push a temporarily clip rectangle in their code. Calling BeginDragDropTargetCustom(LastItemRect) would not handle them.
// 2) and it's faster. as this code may be very frequently called, we want to early out as fast as we can.
// Also note how the HoveredWindow test is positioned differently in both functions (in both functions we optimize for the cheapest early out case)
bool ImGui::BeginDragDropTarget()
{
    ImGuiContext& g = *GImGui;
    if (!g.DragDropActive)
        return false;

    ImGuiWindow* window = g.CurrentWindow;
    if (!(g.LastItemData.StatusFlags & ImGuiItemStatusFlags_HoveredRect))
        return false;
    ImGuiWindow* hovered_window = g.HoveredWindowUnderMovingWindow;
    if (hovered_window == NULL || window->RootWindowDockTree != hovered_window->RootWindowDockTree || window->SkipItems)
        return false;

    const ImRect& display_rect = (g.LastItemData.StatusFlags & ImGuiItemStatusFlags_HasDisplayRect) ? g.LastItemData.DisplayRect : g.LastItemData.Rect;
    ImGuiID id = g.LastItemData.ID;
    if (id == 0)
    {
        id = window->GetIDFromRectangle(display_rect);
        KeepAliveID(id);
    }
    if (g.DragDropPayload.SourceId == id)
        return false;

    IM_ASSERT(g.DragDropWithinTarget == false);
    g.DragDropTargetRect = display_rect;
    g.DragDropTargetId = id;
    g.DragDropWithinTarget = true;
    return true;
}

bool ImGui::IsDragDropPayloadBeingAccepted()
{
    ImGuiContext& g = *GImGui;
    return g.DragDropActive && g.DragDropAcceptIdPrev != 0;
}

const ImGuiPayload* ImGui::AcceptDragDropPayload(const char* type, ImGuiDragDropFlags flags)
{
    ImGuiContext& g = *GImGui;
    ImGuiPayload& payload = g.DragDropPayload;
    IM_ASSERT(g.DragDropActive);                        // Not called between BeginDragDropTarget() and EndDragDropTarget() ?
    IM_ASSERT(payload.DataFrameCount != -1);            // Forgot to call EndDragDropTarget() ?
    if (type != NULL && !payload.IsDataType(type))
        return NULL;

    // Accept smallest drag target bounding box, this allows us to nest drag targets conveniently without ordering constraints.
    // NB: We currently accept NULL id as target. However, overlapping targets requires a unique ID to function!
    const bool was_accepted_previously = (g.DragDropAcceptIdPrev == g.DragDropTargetId);
    ImRect r = g.DragDropTargetRect;
    float r_surface = r.GetWidth() * r.GetHeight();
    if (r_surface > g.DragDropAcceptIdCurrRectSurface)
        return NULL;

    g.DragDropAcceptFlags = flags;
    g.DragDropAcceptIdCurr = g.DragDropTargetId;
    g.DragDropAcceptIdCurrRectSurface = r_surface;
    //IMGUI_DEBUG_LOG("AcceptDragDropPayload(): %08X: accept\n", g.DragDropTargetId);

    // Render default drop visuals
    payload.Preview = was_accepted_previously;
    flags |= (g.DragDropSourceFlags & ImGuiDragDropFlags_AcceptNoDrawDefaultRect); // Source can also inhibit the preview (useful for external sources that live for 1 frame)
    if (!(flags & ImGuiDragDropFlags_AcceptNoDrawDefaultRect) && payload.Preview)
        RenderDragDropTargetRect(r);

    g.DragDropAcceptFrameCount = g.FrameCount;
    payload.Delivery = was_accepted_previously && !IsMouseDown(g.DragDropMouseButton); // For extern drag sources affecting OS window focus, it's easier to just test !IsMouseDown() instead of IsMouseReleased()
    if (!payload.Delivery && !(flags & ImGuiDragDropFlags_AcceptBeforeDelivery))
        return NULL;

    //IMGUI_DEBUG_LOG("AcceptDragDropPayload(): %08X: return payload\n", g.DragDropTargetId);
    return &payload;
}

// FIXME-STYLE FIXME-DRAGDROP: Settle on a proper default visuals for drop target.
void ImGui::RenderDragDropTargetRect(const ImRect& bb)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    ImRect bb_display = bb;
    bb_display.ClipWith(window->ClipRect); // Clip THEN expand so we have a way to visualize that target is not entirely visible.
    bb_display.Expand(3.5f);
    bool push_clip_rect = !window->ClipRect.Contains(bb_display);
    if (push_clip_rect)
        window->DrawList->PushClipRectFullScreen();
    window->DrawList->AddRect(bb_display.Min, bb_display.Max, GetColorU32(ImGuiCol_DragDropTarget), 0.0f, 0, 2.0f);
    if (push_clip_rect)
        window->DrawList->PopClipRect();
}

const ImGuiPayload* ImGui::GetDragDropPayload()
{
    ImGuiContext& g = *GImGui;
    return (g.DragDropActive && g.DragDropPayload.DataFrameCount != -1) ? &g.DragDropPayload : NULL;
}

void ImGui::EndDragDropTarget()
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(g.DragDropActive);
    IM_ASSERT(g.DragDropWithinTarget);
    g.DragDropWithinTarget = false;

    // Clear drag and drop state payload right after delivery
    if (g.DragDropPayload.Delivery)
        ClearDragDrop();
}

//-----------------------------------------------------------------------------
// [SECTION] LOGGING/CAPTURING
//-----------------------------------------------------------------------------
// All text output from the interface can be captured into tty/file/clipboard.
// By default, tree nodes are automatically opened during logging.
//-----------------------------------------------------------------------------

// Pass text data straight to log (without being displayed)
static inline void LogTextV(ImGuiContext& g, const char* fmt, va_list args)
{
    if (g.LogFile)
    {
        g.LogBuffer.Buf.resize(0);
        g.LogBuffer.appendfv(fmt, args);
        ImFileWrite(g.LogBuffer.c_str(), sizeof(char), (ImU64)g.LogBuffer.size(), g.LogFile);
    }
    else
    {
        g.LogBuffer.appendfv(fmt, args);
    }
}

void ImGui::LogText(const char* fmt, ...)
{
    ImGuiContext& g = *GImGui;
    if (!g.LogEnabled)
        return;

    va_list args;
    va_start(args, fmt);
    LogTextV(g, fmt, args);
    va_end(args);
}

void ImGui::LogTextV(const char* fmt, va_list args)
{
    ImGuiContext& g = *GImGui;
    if (!g.LogEnabled)
        return;

    LogTextV(g, fmt, args);
}

// Internal version that takes a position to decide on newline placement and pad items according to their depth.
// We split text into individual lines to add current tree level padding
// FIXME: This code is a little complicated perhaps, considering simplifying the whole system.
void ImGui::LogRenderedText(const ImVec2* ref_pos, const char* text, const char* text_end)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;

    const char* prefix = g.LogNextPrefix;
    const char* suffix = g.LogNextSuffix;
    g.LogNextPrefix = g.LogNextSuffix = NULL;

    if (!text_end)
        text_end = FindRenderedTextEnd(text, text_end);

    const bool log_new_line = ref_pos && (ref_pos->y > g.LogLinePosY + g.Style.FramePadding.y + 1);
    if (ref_pos)
        g.LogLinePosY = ref_pos->y;
    if (log_new_line)
    {
        LogText(IM_NEWLINE);
        g.LogLineFirstItem = true;
    }

    if (prefix)
        LogRenderedText(ref_pos, prefix, prefix + strlen(prefix)); // Calculate end ourself to ensure "##" are included here.

    // Re-adjust padding if we have popped out of our starting depth
    if (g.LogDepthRef > window->DC.TreeDepth)
        g.LogDepthRef = window->DC.TreeDepth;
    const int tree_depth = (window->DC.TreeDepth - g.LogDepthRef);

    const char* text_remaining = text;
    for (;;)
    {
        // Split the string. Each new line (after a '\n') is followed by indentation corresponding to the current depth of our log entry.
        // We don't add a trailing \n yet to allow a subsequent item on the same line to be captured.
        const char* line_start = text_remaining;
        const char* line_end = ImStreolRange(line_start, text_end);
        const bool is_last_line = (line_end == text_end);
        if (line_start != line_end || !is_last_line)
        {
            const int line_length = (int)(line_end - line_start);
            const int indentation = g.LogLineFirstItem ? tree_depth * 4 : 1;
            LogText("%*s%.*s", indentation, "", line_length, line_start);
            g.LogLineFirstItem = false;
            if (*line_end == '\n')
            {
                LogText(IM_NEWLINE);
                g.LogLineFirstItem = true;
            }
        }
        if (is_last_line)
            break;
        text_remaining = line_end + 1;
    }

    if (suffix)
        LogRenderedText(ref_pos, suffix, suffix + strlen(suffix));
}

// Start logging/capturing text output
void ImGui::LogBegin(ImGuiLogType type, int auto_open_depth)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    IM_ASSERT(g.LogEnabled == false);
    IM_ASSERT(g.LogFile == NULL);
    IM_ASSERT(g.LogBuffer.empty());
    g.LogEnabled = true;
    g.LogType = type;
    g.LogNextPrefix = g.LogNextSuffix = NULL;
    g.LogDepthRef = window->DC.TreeDepth;
    g.LogDepthToExpand = ((auto_open_depth >= 0) ? auto_open_depth : g.LogDepthToExpandDefault);
    g.LogLinePosY = FLT_MAX;
    g.LogLineFirstItem = true;
}

// Important: doesn't copy underlying data, use carefully (prefix/suffix must be in scope at the time of the next LogRenderedText)
void ImGui::LogSetNextTextDecoration(const char* prefix, const char* suffix)
{
    ImGuiContext& g = *GImGui;
    g.LogNextPrefix = prefix;
    g.LogNextSuffix = suffix;
}

void ImGui::LogToTTY(int auto_open_depth)
{
    ImGuiContext& g = *GImGui;
    if (g.LogEnabled)
        return;
    IM_UNUSED(auto_open_depth);
#ifndef IMGUI_DISABLE_TTY_FUNCTIONS
    LogBegin(ImGuiLogType_TTY, auto_open_depth);
    g.LogFile = stdout;
#endif
}

// Start logging/capturing text output to given file
void ImGui::LogToFile(int auto_open_depth, const char* filename)
{
    ImGuiContext& g = *GImGui;
    if (g.LogEnabled)
        return;

    // FIXME: We could probably open the file in text mode "at", however note that clipboard/buffer logging will still
    // be subject to outputting OS-incompatible carriage return if within strings the user doesn't use IM_NEWLINE.
    // By opening the file in binary mode "ab" we have consistent output everywhere.
    if (!filename)
        filename = g.IO.LogFilename;
    if (!filename || !filename[0])
        return;
    ImFileHandle f = ImFileOpen(filename, "ab");
    if (!f)
    {
        IM_ASSERT(0);
        return;
    }

    LogBegin(ImGuiLogType_File, auto_open_depth);
    g.LogFile = f;
}

// Start logging/capturing text output to clipboard
void ImGui::LogToClipboard(int auto_open_depth)
{
    ImGuiContext& g = *GImGui;
    if (g.LogEnabled)
        return;
    LogBegin(ImGuiLogType_Clipboard, auto_open_depth);
}

void ImGui::LogToBuffer(int auto_open_depth)
{
    ImGuiContext& g = *GImGui;
    if (g.LogEnabled)
        return;
    LogBegin(ImGuiLogType_Buffer, auto_open_depth);
}

void ImGui::LogFinish()
{
    ImGuiContext& g = *GImGui;
    if (!g.LogEnabled)
        return;

    LogText(IM_NEWLINE);
    switch (g.LogType)
    {
    case ImGuiLogType_TTY:
#ifndef IMGUI_DISABLE_TTY_FUNCTIONS
        fflush(g.LogFile);
#endif
        break;
    case ImGuiLogType_File:
        ImFileClose(g.LogFile);
        break;
    case ImGuiLogType_Buffer:
        break;
    case ImGuiLogType_Clipboard:
        if (!g.LogBuffer.empty())
            SetClipboardText(g.LogBuffer.begin());
        break;
    case ImGuiLogType_None:
        IM_ASSERT(0);
        break;
    }

    g.LogEnabled = false;
    g.LogType = ImGuiLogType_None;
    g.LogFile = NULL;
    g.LogBuffer.clear();
}

// Helper to display logging buttons
// FIXME-OBSOLETE: We should probably obsolete this and let the user have their own helper (this is one of the oldest function alive!)
void ImGui::LogButtons()
{
    ImGuiContext& g = *GImGui;

    PushID("LogButtons");
#ifndef IMGUI_DISABLE_TTY_FUNCTIONS
    const bool log_to_tty = Button("Log To TTY"); SameLine();
#else
    const bool log_to_tty = false;
#endif
    const bool log_to_file = Button("Log To File"); SameLine();
    const bool log_to_clipboard = Button("Log To Clipboard"); SameLine();
    PushTabStop(false);
    SetNextItemWidth(80.0f);
    SliderInt("Default Depth", &g.LogDepthToExpandDefault, 0, 9, NULL);
    PopTabStop();
    PopID();

    // Start logging at the end of the function so that the buttons don't appear in the log
    if (log_to_tty)
        LogToTTY();
    if (log_to_file)
        LogToFile();
    if (log_to_clipboard)
        LogToClipboard();
}


//-----------------------------------------------------------------------------
// [SECTION] SETTINGS
//-----------------------------------------------------------------------------
// - UpdateSettings() [Internal]
// - MarkIniSettingsDirty() [Internal]
// - FindSettingsHandler() [Internal]
// - ClearIniSettings() [Internal]
// - LoadIniSettingsFromDisk()
// - LoadIniSettingsFromMemory()
// - SaveIniSettingsToDisk()
// - SaveIniSettingsToMemory()
//-----------------------------------------------------------------------------
// - CreateNewWindowSettings() [Internal]
// - FindWindowSettingsByID() [Internal]
// - FindWindowSettingsByWindow() [Internal]
// - ClearWindowSettings() [Internal]
// - WindowSettingsHandler_***() [Internal]
//-----------------------------------------------------------------------------

// Called by NewFrame()
void ImGui::UpdateSettings()
{
    // Load settings on first frame (if not explicitly loaded manually before)
    ImGuiContext& g = *GImGui;
    if (!g.SettingsLoaded)
    {
        IM_ASSERT(g.SettingsWindows.empty());
        if (g.IO.IniFilename)
            LoadIniSettingsFromDisk(g.IO.IniFilename);
        g.SettingsLoaded = true;
    }

    // Save settings (with a delay after the last modification, so we don't spam disk too much)
    if (g.SettingsDirtyTimer > 0.0f)
    {
        g.SettingsDirtyTimer -= g.IO.DeltaTime;
        if (g.SettingsDirtyTimer <= 0.0f)
        {
            if (g.IO.IniFilename != NULL)
                SaveIniSettingsToDisk(g.IO.IniFilename);
            else
                g.IO.WantSaveIniSettings = true;  // Let user know they can call SaveIniSettingsToMemory(). user will need to clear io.WantSaveIniSettings themselves.
            g.SettingsDirtyTimer = 0.0f;
        }
    }
}

void ImGui::MarkIniSettingsDirty()
{
    ImGuiContext& g = *GImGui;
    if (g.SettingsDirtyTimer <= 0.0f)
        g.SettingsDirtyTimer = g.IO.IniSavingRate;
}

void ImGui::MarkIniSettingsDirty(ImGuiWindow* window)
{
    ImGuiContext& g = *GImGui;
    if (!(window->Flags & ImGuiWindowFlags_NoSavedSettings))
        if (g.SettingsDirtyTimer <= 0.0f)
            g.SettingsDirtyTimer = g.IO.IniSavingRate;
}

void ImGui::AddSettingsHandler(const ImGuiSettingsHandler* handler)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(FindSettingsHandler(handler->TypeName) == NULL);
    g.SettingsHandlers.push_back(*handler);
}

void ImGui::RemoveSettingsHandler(const char* type_name)
{
    ImGuiContext& g = *GImGui;
    if (ImGuiSettingsHandler* handler = FindSettingsHandler(type_name))
        g.SettingsHandlers.erase(handler);
}

ImGuiSettingsHandler* ImGui::FindSettingsHandler(const char* type_name)
{
    ImGuiContext& g = *GImGui;
    const ImGuiID type_hash = ImHashStr(type_name);
    for (ImGuiSettingsHandler& handler : g.SettingsHandlers)
        if (handler.TypeHash == type_hash)
            return &handler;
    return NULL;
}

// Clear all settings (windows, tables, docking etc.)
void ImGui::ClearIniSettings()
{
    ImGuiContext& g = *GImGui;
    g.SettingsIniData.clear();
    for (ImGuiSettingsHandler& handler : g.SettingsHandlers)
        if (handler.ClearAllFn != NULL)
            handler.ClearAllFn(&g, &handler);
}

void ImGui::LoadIniSettingsFromDisk(const char* ini_filename)
{
    size_t file_data_size = 0;
    char* file_data = (char*)ImFileLoadToMemory(ini_filename, "rb", &file_data_size);
    if (!file_data)
        return;
    if (file_data_size > 0)
        LoadIniSettingsFromMemory(file_data, (size_t)file_data_size);
    IM_FREE(file_data);
}

// Zero-tolerance, no error reporting, cheap .ini parsing
// Set ini_size==0 to let us use strlen(ini_data). Do not call this function with a 0 if your buffer is actually empty!
void ImGui::LoadIniSettingsFromMemory(const char* ini_data, size_t ini_size)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(g.Initialized);
    //IM_ASSERT(!g.WithinFrameScope && "Cannot be called between NewFrame() and EndFrame()");
    //IM_ASSERT(g.SettingsLoaded == false && g.FrameCount == 0);

    // For user convenience, we allow passing a non zero-terminated string (hence the ini_size parameter).
    // For our convenience and to make the code simpler, we'll also write zero-terminators within the buffer. So let's create a writable copy..
    if (ini_size == 0)
        ini_size = strlen(ini_data);
    g.SettingsIniData.Buf.resize((int)ini_size + 1);
    char* const buf = g.SettingsIniData.Buf.Data;
    char* const buf_end = buf + ini_size;
    memcpy(buf, ini_data, ini_size);
    buf_end[0] = 0;

    // Call pre-read handlers
    // Some types will clear their data (e.g. dock information) some types will allow merge/override (window)
    for (ImGuiSettingsHandler& handler : g.SettingsHandlers)
        if (handler.ReadInitFn != NULL)
            handler.ReadInitFn(&g, &handler);

    void* entry_data = NULL;
    ImGuiSettingsHandler* entry_handler = NULL;

    char* line_end = NULL;
    for (char* line = buf; line < buf_end; line = line_end + 1)
    {
        // Skip new lines markers, then find end of the line
        while (*line == '\n' || *line == '\r')
            line++;
        line_end = line;
        while (line_end < buf_end && *line_end != '\n' && *line_end != '\r')
            line_end++;
        line_end[0] = 0;
        if (line[0] == ';')
            continue;
        if (line[0] == '[' && line_end > line && line_end[-1] == ']')
        {
            // Parse "[Type][Name]". Note that 'Name' can itself contains [] characters, which is acceptable with the current format and parsing code.
            line_end[-1] = 0;
            const char* name_end = line_end - 1;
            const char* type_start = line + 1;
            char* type_end = (char*)(void*)ImStrchrRange(type_start, name_end, ']');
            const char* name_start = type_end ? ImStrchrRange(type_end + 1, name_end, '[') : NULL;
            if (!type_end || !name_start)
                continue;
            *type_end = 0; // Overwrite first ']'
            name_start++;  // Skip second '['
            entry_handler = FindSettingsHandler(type_start);
            entry_data = entry_handler ? entry_handler->ReadOpenFn(&g, entry_handler, name_start) : NULL;
        }
        else if (entry_handler != NULL && entry_data != NULL)
        {
            // Let type handler parse the line
            entry_handler->ReadLineFn(&g, entry_handler, entry_data, line);
        }
    }
    g.SettingsLoaded = true;

    // [DEBUG] Restore untouched copy so it can be browsed in Metrics (not strictly necessary)
    memcpy(buf, ini_data, ini_size);

    // Call post-read handlers
    for (ImGuiSettingsHandler& handler : g.SettingsHandlers)
        if (handler.ApplyAllFn != NULL)
            handler.ApplyAllFn(&g, &handler);
}

void ImGui::SaveIniSettingsToDisk(const char* ini_filename)
{
    ImGuiContext& g = *GImGui;
    g.SettingsDirtyTimer = 0.0f;
    if (!ini_filename)
        return;

    size_t ini_data_size = 0;
    const char* ini_data = SaveIniSettingsToMemory(&ini_data_size);
    ImFileHandle f = ImFileOpen(ini_filename, "wt");
    if (!f)
        return;
    ImFileWrite(ini_data, sizeof(char), ini_data_size, f);
    ImFileClose(f);
}

// Call registered handlers (e.g. SettingsHandlerWindow_WriteAll() + custom handlers) to write their stuff into a text buffer
const char* ImGui::SaveIniSettingsToMemory(size_t* out_size)
{
    ImGuiContext& g = *GImGui;
    g.SettingsDirtyTimer = 0.0f;
    g.SettingsIniData.Buf.resize(0);
    g.SettingsIniData.Buf.push_back(0);
    for (ImGuiSettingsHandler& handler : g.SettingsHandlers)
        handler.WriteAllFn(&g, &handler, &g.SettingsIniData);
    if (out_size)
        *out_size = (size_t)g.SettingsIniData.size();
    return g.SettingsIniData.c_str();
}

ImGuiWindowSettings* ImGui::CreateNewWindowSettings(const char* name)
{
    ImGuiContext& g = *GImGui;

    if (g.IO.ConfigDebugIniSettings == false)
    {
        // Skip to the "###" marker if any. We don't skip past to match the behavior of GetID()
        // Preserve the full string when ConfigDebugVerboseIniSettings is set to make .ini inspection easier.
        if (const char* p = strstr(name, "###"))
            name = p;
    }
    const size_t name_len = strlen(name);

    // Allocate chunk
    const size_t chunk_size = sizeof(ImGuiWindowSettings) + name_len + 1;
    ImGuiWindowSettings* settings = g.SettingsWindows.alloc_chunk(chunk_size);
    IM_PLACEMENT_NEW(settings) ImGuiWindowSettings();
    settings->ID = ImHashStr(name, name_len);
    memcpy(settings->GetName(), name, name_len + 1);   // Store with zero terminator

    return settings;
}

// We don't provide a FindWindowSettingsByName() because Docking system doesn't always hold on names.
// This is called once per window .ini entry + once per newly instantiated window.
ImGuiWindowSettings* ImGui::FindWindowSettingsByID(ImGuiID id)
{
    ImGuiContext& g = *GImGui;
    for (ImGuiWindowSettings* settings = g.SettingsWindows.begin(); settings != NULL; settings = g.SettingsWindows.next_chunk(settings))
        if (settings->ID == id && !settings->WantDelete)
            return settings;
    return NULL;
}

// This is faster if you are holding on a Window already as we don't need to perform a search.
ImGuiWindowSettings* ImGui::FindWindowSettingsByWindow(ImGuiWindow* window)
{
    ImGuiContext& g = *GImGui;
    if (window->SettingsOffset != -1)
        return g.SettingsWindows.ptr_from_offset(window->SettingsOffset);
    return FindWindowSettingsByID(window->ID);
}

// This will revert window to its initial state, including enabling the ImGuiCond_FirstUseEver/ImGuiCond_Once conditions once more.
void ImGui::ClearWindowSettings(const char* name)
{
    //IMGUI_DEBUG_LOG("ClearWindowSettings('%s')\n", name);
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = FindWindowByName(name);
    if (window != NULL)
    {
        window->Flags |= ImGuiWindowFlags_NoSavedSettings;
        InitOrLoadWindowSettings(window, NULL);
        if (window->DockId != 0)
            DockContextProcessUndockWindow(&g, window, true);
    }
    if (ImGuiWindowSettings* settings = window ? FindWindowSettingsByWindow(window) : FindWindowSettingsByID(ImHashStr(name)))
        settings->WantDelete = true;
}

static void WindowSettingsHandler_ClearAll(ImGuiContext* ctx, ImGuiSettingsHandler*)
{
    ImGuiContext& g = *ctx;
    for (ImGuiWindow* window : g.Windows)
        window->SettingsOffset = -1;
    g.SettingsWindows.clear();
}

static void* WindowSettingsHandler_ReadOpen(ImGuiContext*, ImGuiSettingsHandler*, const char* name)
{
    ImGuiID id = ImHashStr(name);
    ImGuiWindowSettings* settings = ImGui::FindWindowSettingsByID(id);
    if (settings)
        *settings = ImGuiWindowSettings(); // Clear existing if recycling previous entry
    else
        settings = ImGui::CreateNewWindowSettings(name);
    settings->ID = id;
    settings->WantApply = true;
    return (void*)settings;
}

static void WindowSettingsHandler_ReadLine(ImGuiContext*, ImGuiSettingsHandler*, void* entry, const char* line)
{
    ImGuiWindowSettings* settings = (ImGuiWindowSettings*)entry;
    int x, y;
    int i;
    ImU32 u1;
    if (sscanf(line, "Pos=%i,%i", &x, &y) == 2)             { settings->Pos = ImVec2ih((short)x, (short)y); }
    else if (sscanf(line, "Size=%i,%i", &x, &y) == 2)       { settings->Size = ImVec2ih((short)x, (short)y); }
    else if (sscanf(line, "ViewportId=0x%08X", &u1) == 1)   { settings->ViewportId = u1; }
    else if (sscanf(line, "ViewportPos=%i,%i", &x, &y) == 2){ settings->ViewportPos = ImVec2ih((short)x, (short)y); }
    else if (sscanf(line, "Collapsed=%d", &i) == 1)         { settings->Collapsed = (i != 0); }
    else if (sscanf(line, "IsChild=%d", &i) == 1)           { settings->IsChild = (i != 0); }
    else if (sscanf(line, "DockId=0x%X,%d", &u1, &i) == 2)  { settings->DockId = u1; settings->DockOrder = (short)i; }
    else if (sscanf(line, "DockId=0x%X", &u1) == 1)         { settings->DockId = u1; settings->DockOrder = -1; }
    else if (sscanf(line, "ClassId=0x%X", &u1) == 1)        { settings->ClassId = u1; }
}

// Apply to existing windows (if any)
static void WindowSettingsHandler_ApplyAll(ImGuiContext* ctx, ImGuiSettingsHandler*)
{
    ImGuiContext& g = *ctx;
    for (ImGuiWindowSettings* settings = g.SettingsWindows.begin(); settings != NULL; settings = g.SettingsWindows.next_chunk(settings))
        if (settings->WantApply)
        {
            if (ImGuiWindow* window = ImGui::FindWindowByID(settings->ID))
                ApplyWindowSettings(window, settings);
            settings->WantApply = false;
        }
}

static void WindowSettingsHandler_WriteAll(ImGuiContext* ctx, ImGuiSettingsHandler* handler, ImGuiTextBuffer* buf)
{
    // Gather data from windows that were active during this session
    // (if a window wasn't opened in this session we preserve its settings)
    ImGuiContext& g = *ctx;
    for (ImGuiWindow* window : g.Windows)
    {
        if (window->Flags & ImGuiWindowFlags_NoSavedSettings)
            continue;

        ImGuiWindowSettings* settings = ImGui::FindWindowSettingsByWindow(window);
        if (!settings)
        {
            settings = ImGui::CreateNewWindowSettings(window->Name);
            window->SettingsOffset = g.SettingsWindows.offset_from_ptr(settings);
        }
        IM_ASSERT(settings->ID == window->ID);
        settings->Pos = ImVec2ih(window->Pos - window->ViewportPos);
        settings->Size = ImVec2ih(window->SizeFull);
        settings->ViewportId = window->ViewportId;
        settings->ViewportPos = ImVec2ih(window->ViewportPos);
        IM_ASSERT(window->DockNode == NULL || window->DockNode->ID == window->DockId);
        settings->DockId = window->DockId;
        settings->ClassId = window->WindowClass.ClassId;
        settings->DockOrder = window->DockOrder;
        settings->Collapsed = window->Collapsed;
        settings->IsChild = (window->RootWindow != window); // Cannot rely on ImGuiWindowFlags_ChildWindow here as docked windows have this set.
        settings->WantDelete = false;
    }

    // Write to text buffer
    buf->reserve(buf->size() + g.SettingsWindows.size() * 6); // ballpark reserve
    for (ImGuiWindowSettings* settings = g.SettingsWindows.begin(); settings != NULL; settings = g.SettingsWindows.next_chunk(settings))
    {
        if (settings->WantDelete)
            continue;
        const char* settings_name = settings->GetName();
        buf->appendf("[%s][%s]\n", handler->TypeName, settings_name);
        if (settings->IsChild)
        {
            buf->appendf("IsChild=1\n");
            buf->appendf("Size=%d,%d\n", settings->Size.x, settings->Size.y);
        }
        else
        {
            if (settings->ViewportId != 0 && settings->ViewportId != ImGui::IMGUI_VIEWPORT_DEFAULT_ID)
            {
                buf->appendf("ViewportPos=%d,%d\n", settings->ViewportPos.x, settings->ViewportPos.y);
                buf->appendf("ViewportId=0x%08X\n", settings->ViewportId);
            }
            if (settings->Pos.x != 0 || settings->Pos.y != 0 || settings->ViewportId == ImGui::IMGUI_VIEWPORT_DEFAULT_ID)
                buf->appendf("Pos=%d,%d\n", settings->Pos.x, settings->Pos.y);
            if (settings->Size.x != 0 || settings->Size.y != 0)
                buf->appendf("Size=%d,%d\n", settings->Size.x, settings->Size.y);
            buf->appendf("Collapsed=%d\n", settings->Collapsed);
            if (settings->DockId != 0)
            {
                //buf->appendf("TabId=0x%08X\n", ImHashStr("#TAB", 4, settings->ID)); // window->TabId: this is not read back but writing it makes "debugging" the .ini data easier.
                if (settings->DockOrder == -1)
                    buf->appendf("DockId=0x%08X\n", settings->DockId);
                else
                    buf->appendf("DockId=0x%08X,%d\n", settings->DockId, settings->DockOrder);
                if (settings->ClassId != 0)
                    buf->appendf("ClassId=0x%08X\n", settings->ClassId);
            }
        }
        buf->append("\n");
    }
}


//-----------------------------------------------------------------------------
// [SECTION] LOCALIZATION
//-----------------------------------------------------------------------------

void ImGui::LocalizeRegisterEntries(const ImGuiLocEntry* entries, int count)
{
    ImGuiContext& g = *GImGui;
    for (int n = 0; n < count; n++)
        g.LocalizationTable[entries[n].Key] = entries[n].Text;
}


//-----------------------------------------------------------------------------
// [SECTION] VIEWPORTS, PLATFORM WINDOWS
//-----------------------------------------------------------------------------
// - GetMainViewport()
// - FindViewportByID()
// - FindViewportByPlatformHandle()
// - SetCurrentViewport() [Internal]
// - SetWindowViewport() [Internal]
// - GetWindowAlwaysWantOwnViewport() [Internal]
// - UpdateTryMergeWindowIntoHostViewport() [Internal]
// - UpdateTryMergeWindowIntoHostViewports() [Internal]
// - TranslateWindowsInViewport() [Internal]
// - ScaleWindowsInViewport() [Internal]
// - FindHoveredViewportFromPlatformWindowStack() [Internal]
// - UpdateViewportsNewFrame() [Internal]
// - UpdateViewportsEndFrame() [Internal]
// - AddUpdateViewport() [Internal]
// - WindowSelectViewport() [Internal]
// - WindowSyncOwnedViewport() [Internal]
// - UpdatePlatformWindows()
// - RenderPlatformWindowsDefault()
// - FindPlatformMonitorForPos() [Internal]
// - FindPlatformMonitorForRect() [Internal]
// - UpdateViewportPlatformMonitor() [Internal]
// - DestroyPlatformWindow() [Internal]
// - DestroyPlatformWindows()
//-----------------------------------------------------------------------------

ImGuiViewport* ImGui::GetMainViewport()
{
    ImGuiContext& g = *GImGui;
    return g.Viewports[0];
}

// FIXME: This leaks access to viewports not listed in PlatformIO.Viewports[]. Problematic? (#4236)
ImGuiViewport* ImGui::FindViewportByID(ImGuiID id)
{
    ImGuiContext& g = *GImGui;
    for (ImGuiViewportP* viewport : g.Viewports)
        if (viewport->ID == id)
            return viewport;
    return NULL;
}

ImGuiViewport* ImGui::FindViewportByPlatformHandle(void* platform_handle)
{
    ImGuiContext& g = *GImGui;
    for (ImGuiViewportP* viewport : g.Viewports)
        if (viewport->PlatformHandle == platform_handle)
            return viewport;
    return NULL;
}

void ImGui::SetCurrentViewport(ImGuiWindow* current_window, ImGuiViewportP* viewport)
{
    ImGuiContext& g = *GImGui;
    (void)current_window;

    if (viewport)
        viewport->LastFrameActive = g.FrameCount;
    if (g.CurrentViewport == viewport)
        return;
    g.CurrentDpiScale = viewport ? viewport->DpiScale : 1.0f;
    g.CurrentViewport = viewport;
    //IMGUI_DEBUG_LOG_VIEWPORT("[viewport] SetCurrentViewport changed '%s' 0x%08X\n", current_window ? current_window->Name : NULL, viewport ? viewport->ID : 0);

    // Notify platform layer of viewport changes
    // FIXME-DPI: This is only currently used for experimenting with handling of multiple DPI
    if (g.CurrentViewport && g.PlatformIO.Platform_OnChangedViewport)
        g.PlatformIO.Platform_OnChangedViewport(g.CurrentViewport);
}

void ImGui::SetWindowViewport(ImGuiWindow* window, ImGuiViewportP* viewport)
{
    // Abandon viewport
    if (window->ViewportOwned && window->Viewport->Window == window)
        window->Viewport->Size = ImVec2(0.0f, 0.0f);

    window->Viewport = viewport;
    window->ViewportId = viewport->ID;
    window->ViewportOwned = (viewport->Window == window);
}

static bool ImGui::GetWindowAlwaysWantOwnViewport(ImGuiWindow* window)
{
    // Tooltips and menus are not automatically forced into their own viewport when the NoMerge flag is set, however the multiplication of viewports makes them more likely to protrude and create their own.
    ImGuiContext& g = *GImGui;
    if (g.IO.ConfigViewportsNoAutoMerge || (window->WindowClass.ViewportFlagsOverrideSet & ImGuiViewportFlags_NoAutoMerge))
        if (g.ConfigFlagsCurrFrame & ImGuiConfigFlags_ViewportsEnable)
            if (!window->DockIsActive)
                if ((window->Flags & (ImGuiWindowFlags_ChildWindow | ImGuiWindowFlags_ChildMenu | ImGuiWindowFlags_Tooltip)) == 0)
                    if ((window->Flags & ImGuiWindowFlags_Popup) == 0 || (window->Flags & ImGuiWindowFlags_Modal) != 0)
                        return true;
    return false;
}

static bool ImGui::UpdateTryMergeWindowIntoHostViewport(ImGuiWindow* window, ImGuiViewportP* viewport)
{
    ImGuiContext& g = *GImGui;
    if (window->Viewport == viewport)
        return false;
    if ((viewport->Flags & ImGuiViewportFlags_CanHostOtherWindows) == 0)
        return false;
    if ((viewport->Flags & ImGuiViewportFlags_IsMinimized) != 0)
        return false;
    if (!viewport->GetMainRect().Contains(window->Rect()))
        return false;
    if (GetWindowAlwaysWantOwnViewport(window))
        return false;

    // FIXME: Can't use g.WindowsFocusOrder[] for root windows only as we care about Z order. If we maintained a DisplayOrder along with FocusOrder we could..
    for (ImGuiWindow* window_behind : g.Windows)
    {
        if (window_behind == window)
            break;
        if (window_behind->WasActive && window_behind->ViewportOwned && !(window_behind->Flags & ImGuiWindowFlags_ChildWindow))
            if (window_behind->Viewport->GetMainRect().Overlaps(window->Rect()))
                return false;
    }

    // Move to the existing viewport, Move child/hosted windows as well (FIXME-OPT: iterate child)
    ImGuiViewportP* old_viewport = window->Viewport;
    if (window->ViewportOwned)
        for (int n = 0; n < g.Windows.Size; n++)
            if (g.Windows[n]->Viewport == old_viewport)
                SetWindowViewport(g.Windows[n], viewport);
    SetWindowViewport(window, viewport);
    BringWindowToDisplayFront(window);

    return true;
}

// FIXME: handle 0 to N host viewports
static bool ImGui::UpdateTryMergeWindowIntoHostViewports(ImGuiWindow* window)
{
    ImGuiContext& g = *GImGui;
    return UpdateTryMergeWindowIntoHostViewport(window, g.Viewports[0]);
}

// Translate Dear ImGui windows when a Host Viewport has been moved
// (This additionally keeps windows at the same place when ImGuiConfigFlags_ViewportsEnable is toggled!)
void ImGui::TranslateWindowsInViewport(ImGuiViewportP* viewport, const ImVec2& old_pos, const ImVec2& new_pos)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(viewport->Window == NULL && (viewport->Flags & ImGuiViewportFlags_CanHostOtherWindows));

    // 1) We test if ImGuiConfigFlags_ViewportsEnable was just toggled, which allows us to conveniently
    // translate imgui windows from OS-window-local to absolute coordinates or vice-versa.
    // 2) If it's not going to fit into the new size, keep it at same absolute position.
    // One problem with this is that most Win32 applications doesn't update their render while dragging,
    // and so the window will appear to teleport when releasing the mouse.
    const bool translate_all_windows = (g.ConfigFlagsCurrFrame & ImGuiConfigFlags_ViewportsEnable) != (g.ConfigFlagsLastFrame & ImGuiConfigFlags_ViewportsEnable);
    ImRect test_still_fit_rect(old_pos, old_pos + viewport->Size);
    ImVec2 delta_pos = new_pos - old_pos;
    for (ImGuiWindow* window : g.Windows) // FIXME-OPT
        if (translate_all_windows || (window->Viewport == viewport && test_still_fit_rect.Contains(window->Rect())))
            TranslateWindow(window, delta_pos);
}

// Scale all windows (position, size). Use when e.g. changing DPI. (This is a lossy operation!)
void ImGui::ScaleWindowsInViewport(ImGuiViewportP* viewport, float scale)
{
    ImGuiContext& g = *GImGui;
    if (viewport->Window)
    {
        ScaleWindow(viewport->Window, scale);
    }
    else
    {
        for (ImGuiWindow* window : g.Windows)
            if (window->Viewport == viewport)
                ScaleWindow(window, scale);
    }
}

// If the backend doesn't set MouseLastHoveredViewport or doesn't honor ImGuiViewportFlags_NoInputs, we do a search ourselves.
// A) It won't take account of the possibility that non-imgui windows may be in-between our dragged window and our target window.
// B) It requires Platform_GetWindowFocus to be implemented by backend.
ImGuiViewportP* ImGui::FindHoveredViewportFromPlatformWindowStack(const ImVec2& mouse_platform_pos)
{
    ImGuiContext& g = *GImGui;
    ImGuiViewportP* best_candidate = NULL;
    for (ImGuiViewportP* viewport : g.Viewports)
        if (!(viewport->Flags & (ImGuiViewportFlags_NoInputs | ImGuiViewportFlags_IsMinimized)) && viewport->GetMainRect().Contains(mouse_platform_pos))
            if (best_candidate == NULL || best_candidate->LastFocusedStampCount < viewport->LastFocusedStampCount)
                best_candidate = viewport;
    return best_candidate;
}

// Update viewports and monitor infos
// Note that this is running even if 'ImGuiConfigFlags_ViewportsEnable' is not set, in order to clear unused viewports (if any) and update monitor info.
static void ImGui::UpdateViewportsNewFrame()
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(g.PlatformIO.Viewports.Size <= g.Viewports.Size);

    // Update Minimized status (we need it first in order to decide if we'll apply Pos/Size of the main viewport)
    // Update Focused status
    const bool viewports_enabled = (g.ConfigFlagsCurrFrame & ImGuiConfigFlags_ViewportsEnable) != 0;
    if (viewports_enabled)
    {
        ImGuiViewportP* focused_viewport = NULL;
        for (ImGuiViewportP* viewport : g.Viewports)
        {
            const bool platform_funcs_available = viewport->PlatformWindowCreated;
            if (g.PlatformIO.Platform_GetWindowMinimized && platform_funcs_available)
            {
                bool is_minimized = g.PlatformIO.Platform_GetWindowMinimized(viewport);
                if (is_minimized)
                    viewport->Flags |= ImGuiViewportFlags_IsMinimized;
                else
                    viewport->Flags &= ~ImGuiViewportFlags_IsMinimized;
            }

            // Update our implicit z-order knowledge of platform windows, which is used when the backend cannot provide io.MouseHoveredViewport.
            // When setting Platform_GetWindowFocus, it is expected that the platform backend can handle calls without crashing if it doesn't have data stored.
            if (g.PlatformIO.Platform_GetWindowFocus && platform_funcs_available)
            {
                bool is_focused = g.PlatformIO.Platform_GetWindowFocus(viewport);
                if (is_focused)
                    viewport->Flags |= ImGuiViewportFlags_IsFocused;
                else
                    viewport->Flags &= ~ImGuiViewportFlags_IsFocused;
                if (is_focused)
                    focused_viewport = viewport;
            }
        }

        // Focused viewport has changed?
        if (focused_viewport && g.PlatformLastFocusedViewportId != focused_viewport->ID)
        {
            IMGUI_DEBUG_LOG_VIEWPORT("[viewport] Focused viewport changed %08X -> %08X, attempting to apply our focus.\n", g.PlatformLastFocusedViewportId, focused_viewport->ID);
            const ImGuiViewport* prev_focused_viewport = FindViewportByID(g.PlatformLastFocusedViewportId);
            const bool prev_focused_has_been_destroyed = (prev_focused_viewport == NULL) || (prev_focused_viewport->PlatformWindowCreated == false);

            // Store a tag so we can infer z-order easily from all our windows
            // We compare PlatformLastFocusedViewportId so newly created viewports with _NoFocusOnAppearing flag
            // will keep the front most stamp instead of losing it back to their parent viewport.
            if (focused_viewport->LastFocusedStampCount != g.ViewportFocusedStampCount)
                focused_viewport->LastFocusedStampCount = ++g.ViewportFocusedStampCount;
            g.PlatformLastFocusedViewportId = focused_viewport->ID;

            // Focus associated dear imgui window
            // - if focus didn't happen with a click within imgui boundaries, e.g. Clicking platform title bar. (#6299)
            // - if focus didn't happen because we destroyed another window (#6462)
            // FIXME: perhaps 'FocusTopMostWindowUnderOne()' can handle the 'focused_window->Window != NULL' case as well.
            const bool apply_imgui_focus_on_focused_viewport = !IsAnyMouseDown() && !prev_focused_has_been_destroyed;
            if (apply_imgui_focus_on_focused_viewport)
            {
                focused_viewport->LastFocusedHadNavWindow |= (g.NavWindow != NULL) && (g.NavWindow->Viewport == focused_viewport); // Update so a window changing viewport won't lose focus.
                ImGuiFocusRequestFlags focus_request_flags = ImGuiFocusRequestFlags_UnlessBelowModal | ImGuiFocusRequestFlags_RestoreFocusedChild;
                if (focused_viewport->Window != NULL)
                    FocusWindow(focused_viewport->Window, focus_request_flags);
                else if (focused_viewport->LastFocusedHadNavWindow)
                    FocusTopMostWindowUnderOne(NULL, NULL, focused_viewport, focus_request_flags); // Focus top most in viewport
                else
                    FocusWindow(NULL, focus_request_flags); // No window had focus last time viewport was focused
            }
        }
        if (focused_viewport)
            focused_viewport->LastFocusedHadNavWindow = (g.NavWindow != NULL) && (g.NavWindow->Viewport == focused_viewport);
    }

    // Create/update main viewport with current platform position.
    // FIXME-VIEWPORT: Size is driven by backend/user code for backward-compatibility but we should aim to make this more consistent.
    ImGuiViewportP* main_viewport = g.Viewports[0];
    IM_ASSERT(main_viewport->ID == IMGUI_VIEWPORT_DEFAULT_ID);
    IM_ASSERT(main_viewport->Window == NULL);
    ImVec2 main_viewport_pos = viewports_enabled ? g.PlatformIO.Platform_GetWindowPos(main_viewport) : ImVec2(0.0f, 0.0f);
    ImVec2 main_viewport_size = g.IO.DisplaySize;
    if (viewports_enabled && (main_viewport->Flags & ImGuiViewportFlags_IsMinimized))
    {
        main_viewport_pos = main_viewport->Pos;    // Preserve last pos/size when minimized (FIXME: We don't do the same for Size outside of the viewport path)
        main_viewport_size = main_viewport->Size;
    }
    AddUpdateViewport(NULL, IMGUI_VIEWPORT_DEFAULT_ID, main_viewport_pos, main_viewport_size, ImGuiViewportFlags_OwnedByApp | ImGuiViewportFlags_CanHostOtherWindows);

    g.CurrentDpiScale = 0.0f;
    g.CurrentViewport = NULL;
    g.MouseViewport = NULL;
    for (int n = 0; n < g.Viewports.Size; n++)
    {
        ImGuiViewportP* viewport = g.Viewports[n];
        viewport->Idx = n;

        // Erase unused viewports
        if (n > 0 && viewport->LastFrameActive < g.FrameCount - 2)
        {
            DestroyViewport(viewport);
            n--;
            continue;
        }

        const bool platform_funcs_available = viewport->PlatformWindowCreated;
        if (viewports_enabled)
        {
            // Update Position and Size (from Platform Window to ImGui) if requested.
            // We do it early in the frame instead of waiting for UpdatePlatformWindows() to avoid a frame of lag when moving/resizing using OS facilities.
            if (!(viewport->Flags & ImGuiViewportFlags_IsMinimized) && platform_funcs_available)
            {
                // Viewport->WorkPos and WorkSize will be updated below
                if (viewport->PlatformRequestMove)
                    viewport->Pos = viewport->LastPlatformPos = g.PlatformIO.Platform_GetWindowPos(viewport);
                if (viewport->PlatformRequestResize)
                    viewport->Size = viewport->LastPlatformSize = g.PlatformIO.Platform_GetWindowSize(viewport);
            }
        }

        // Update/copy monitor info
        UpdateViewportPlatformMonitor(viewport);

        // Lock down space taken by menu bars and status bars, reset the offset for functions like BeginMainMenuBar() to alter them again.
        viewport->WorkOffsetMin = viewport->BuildWorkOffsetMin;
        viewport->WorkOffsetMax = viewport->BuildWorkOffsetMax;
        viewport->BuildWorkOffsetMin = viewport->BuildWorkOffsetMax = ImVec2(0.0f, 0.0f);
        viewport->UpdateWorkRect();

        // Reset alpha every frame. Users of transparency (docking) needs to request a lower alpha back.
        viewport->Alpha = 1.0f;

        // Translate Dear ImGui windows when a Host Viewport has been moved
        // (This additionally keeps windows at the same place when ImGuiConfigFlags_ViewportsEnable is toggled!)
        const ImVec2 viewport_delta_pos = viewport->Pos - viewport->LastPos;
        if ((viewport->Flags & ImGuiViewportFlags_CanHostOtherWindows) && (viewport_delta_pos.x != 0.0f || viewport_delta_pos.y != 0.0f))
            TranslateWindowsInViewport(viewport, viewport->LastPos, viewport->Pos);

        // Update DPI scale
        float new_dpi_scale;
        if (g.PlatformIO.Platform_GetWindowDpiScale && platform_funcs_available)
            new_dpi_scale = g.PlatformIO.Platform_GetWindowDpiScale(viewport);
        else if (viewport->PlatformMonitor != -1)
            new_dpi_scale = g.PlatformIO.Monitors[viewport->PlatformMonitor].DpiScale;
        else
            new_dpi_scale = (viewport->DpiScale != 0.0f) ? viewport->DpiScale : 1.0f;
        if (viewport->DpiScale != 0.0f && new_dpi_scale != viewport->DpiScale)
        {
            float scale_factor = new_dpi_scale / viewport->DpiScale;
            if (g.IO.ConfigFlags & ImGuiConfigFlags_DpiEnableScaleViewports)
                ScaleWindowsInViewport(viewport, scale_factor);
            //if (viewport == GetMainViewport())
            //    g.PlatformInterface.SetWindowSize(viewport, viewport->Size * scale_factor);

            // Scale our window moving pivot so that the window will rescale roughly around the mouse position.
            // FIXME-VIEWPORT: This currently creates a resizing feedback loop when a window is straddling a DPI transition border.
            // (Minor: since our sizes do not perfectly linearly scale, deferring the click offset scale until we know the actual window scale ratio may get us slightly more precise mouse positioning.)
            //if (g.MovingWindow != NULL && g.MovingWindow->Viewport == viewport)
            //    g.ActiveIdClickOffset = ImTrunc(g.ActiveIdClickOffset * scale_factor);
        }
        viewport->DpiScale = new_dpi_scale;
    }

    // Update fallback monitor
    if (g.PlatformIO.Monitors.Size == 0)
    {
        ImGuiPlatformMonitor* monitor = &g.FallbackMonitor;
        monitor->MainPos = main_viewport->Pos;
        monitor->MainSize = main_viewport->Size;
        monitor->WorkPos = main_viewport->WorkPos;
        monitor->WorkSize = main_viewport->WorkSize;
        monitor->DpiScale = main_viewport->DpiScale;
    }

    if (!viewports_enabled)
    {
        g.MouseViewport = main_viewport;
        return;
    }

    // Mouse handling: decide on the actual mouse viewport for this frame between the active/focused viewport and the hovered viewport.
    // Note that 'viewport_hovered' should skip over any viewport that has the ImGuiViewportFlags_NoInputs flags set.
    ImGuiViewportP* viewport_hovered = NULL;
    if (g.IO.BackendFlags & ImGuiBackendFlags_HasMouseHoveredViewport)
    {
        viewport_hovered = g.IO.MouseHoveredViewport ? (ImGuiViewportP*)FindViewportByID(g.IO.MouseHoveredViewport) : NULL;
        if (viewport_hovered && (viewport_hovered->Flags & ImGuiViewportFlags_NoInputs))
            viewport_hovered = FindHoveredViewportFromPlatformWindowStack(g.IO.MousePos); // Backend failed to handle _NoInputs viewport: revert to our fallback.
    }
    else
    {
        // If the backend doesn't know how to honor ImGuiViewportFlags_NoInputs, we do a search ourselves. Note that this search:
        // A) won't take account of the possibility that non-imgui windows may be in-between our dragged window and our target window.
        // B) won't take account of how the backend apply parent<>child relationship to secondary viewports, which affects their Z order.
        // C) uses LastFrameAsRefViewport as a flawed replacement for the last time a window was focused (we could/should fix that by introducing Focus functions in PlatformIO)
        viewport_hovered = FindHoveredViewportFromPlatformWindowStack(g.IO.MousePos);
    }
    if (viewport_hovered != NULL)
        g.MouseLastHoveredViewport = viewport_hovered;
    else if (g.MouseLastHoveredViewport == NULL)
        g.MouseLastHoveredViewport = g.Viewports[0];

    // Update mouse reference viewport
    // (when moving a window we aim at its viewport, but this will be overwritten below if we go in drag and drop mode)
    // (MovingViewport->Viewport will be NULL in the rare situation where the window disappared while moving, set UpdateMouseMovingWindowNewFrame() for details)
    if (g.MovingWindow && g.MovingWindow->Viewport)
        g.MouseViewport = g.MovingWindow->Viewport;
    else
        g.MouseViewport = g.MouseLastHoveredViewport;

    // When dragging something, always refer to the last hovered viewport.
    // - when releasing a moving window we will revert to aiming behind (at viewport_hovered)
    // - when we are between viewports, our dragged preview will tend to show in the last viewport _even_ if we don't have tooltips in their viewports (when lacking monitor info)
    // - consider the case of holding on a menu item to browse child menus: even thou a mouse button is held, there's no active id because menu items only react on mouse release.
    // FIXME-VIEWPORT: This is essentially broken, when ImGuiBackendFlags_HasMouseHoveredViewport is set we want to trust when viewport_hovered==NULL and use that.
    const bool is_mouse_dragging_with_an_expected_destination = g.DragDropActive;
    if (is_mouse_dragging_with_an_expected_destination && viewport_hovered == NULL)
        viewport_hovered = g.MouseLastHoveredViewport;
    if (is_mouse_dragging_with_an_expected_destination || g.ActiveId == 0 || !IsAnyMouseDown())
        if (viewport_hovered != NULL && viewport_hovered != g.MouseViewport && !(viewport_hovered->Flags & ImGuiViewportFlags_NoInputs))
            g.MouseViewport = viewport_hovered;

    IM_ASSERT(g.MouseViewport != NULL);
}

// Update user-facing viewport list (g.Viewports -> g.PlatformIO.Viewports after filtering out some)
static void ImGui::UpdateViewportsEndFrame()
{
    ImGuiContext& g = *GImGui;
    g.PlatformIO.Viewports.resize(0);
    for (int i = 0; i < g.Viewports.Size; i++)
    {
        ImGuiViewportP* viewport = g.Viewports[i];
        viewport->LastPos = viewport->Pos;
        if (viewport->LastFrameActive < g.FrameCount || viewport->Size.x <= 0.0f || viewport->Size.y <= 0.0f)
            if (i > 0) // Always include main viewport in the list
                continue;
        if (viewport->Window && !IsWindowActiveAndVisible(viewport->Window))
            continue;
        if (i > 0)
            IM_ASSERT(viewport->Window != NULL);
        g.PlatformIO.Viewports.push_back(viewport);
    }
    g.Viewports[0]->ClearRequestFlags(); // Clear main viewport flags because UpdatePlatformWindows() won't do it and may not even be called
}

// FIXME: We should ideally refactor the system to call this every frame (we currently don't)
ImGuiViewportP* ImGui::AddUpdateViewport(ImGuiWindow* window, ImGuiID id, const ImVec2& pos, const ImVec2& size, ImGuiViewportFlags flags)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(id != 0);

    flags |= ImGuiViewportFlags_IsPlatformWindow;
    if (window != NULL)
    {
        if (g.MovingWindow && g.MovingWindow->RootWindowDockTree == window)
            flags |= ImGuiViewportFlags_NoInputs | ImGuiViewportFlags_NoFocusOnAppearing;
        if ((window->Flags & ImGuiWindowFlags_NoMouseInputs) && (window->Flags & ImGuiWindowFlags_NoNavInputs))
            flags |= ImGuiViewportFlags_NoInputs;
        if (window->Flags & ImGuiWindowFlags_NoFocusOnAppearing)
            flags |= ImGuiViewportFlags_NoFocusOnAppearing;
    }

    ImGuiViewportP* viewport = (ImGuiViewportP*)FindViewportByID(id);
    if (viewport)
    {
        // Always update for main viewport as we are already pulling correct platform pos/size (see #4900)
        if (!viewport->PlatformRequestMove || viewport->ID == IMGUI_VIEWPORT_DEFAULT_ID)
            viewport->Pos = pos;
        if (!viewport->PlatformRequestResize || viewport->ID == IMGUI_VIEWPORT_DEFAULT_ID)
            viewport->Size = size;
        viewport->Flags = flags | (viewport->Flags & (ImGuiViewportFlags_IsMinimized | ImGuiViewportFlags_IsFocused)); // Preserve existing flags
    }
    else
    {
        // New viewport
        viewport = IM_NEW(ImGuiViewportP)();
        viewport->ID = id;
        viewport->Idx = g.Viewports.Size;
        viewport->Pos = viewport->LastPos = pos;
        viewport->Size = size;
        viewport->Flags = flags;
        UpdateViewportPlatformMonitor(viewport);
        g.Viewports.push_back(viewport);
        g.ViewportCreatedCount++;
        IMGUI_DEBUG_LOG_VIEWPORT("[viewport] Add Viewport %08X '%s'\n", id, window ? window->Name : "<NULL>");

        // We normally setup for all viewports in NewFrame() but here need to handle the mid-frame creation of a new viewport.
        // We need to extend the fullscreen clip rect so the OverlayDrawList clip is correct for that the first frame
        g.DrawListSharedData.ClipRectFullscreen.x = ImMin(g.DrawListSharedData.ClipRectFullscreen.x, viewport->Pos.x);
        g.DrawListSharedData.ClipRectFullscreen.y = ImMin(g.DrawListSharedData.ClipRectFullscreen.y, viewport->Pos.y);
        g.DrawListSharedData.ClipRectFullscreen.z = ImMax(g.DrawListSharedData.ClipRectFullscreen.z, viewport->Pos.x + viewport->Size.x);
        g.DrawListSharedData.ClipRectFullscreen.w = ImMax(g.DrawListSharedData.ClipRectFullscreen.w, viewport->Pos.y + viewport->Size.y);

        // Store initial DpiScale before the OS platform window creation, based on expected monitor data.
        // This is so we can select an appropriate font size on the first frame of our window lifetime
        if (viewport->PlatformMonitor != -1)
            viewport->DpiScale = g.PlatformIO.Monitors[viewport->PlatformMonitor].DpiScale;
    }

    viewport->Window = window;
    viewport->LastFrameActive = g.FrameCount;
    viewport->UpdateWorkRect();
    IM_ASSERT(window == NULL || viewport->ID == window->ID);

    if (window != NULL)
        window->ViewportOwned = true;

    return viewport;
}

static void ImGui::DestroyViewport(ImGuiViewportP* viewport)
{
    // Clear references to this viewport in windows (window->ViewportId becomes the master data)
    ImGuiContext& g = *GImGui;
    for (ImGuiWindow* window : g.Windows)
    {
        if (window->Viewport != viewport)
            continue;
        window->Viewport = NULL;
        window->ViewportOwned = false;
    }
    if (viewport == g.MouseLastHoveredViewport)
        g.MouseLastHoveredViewport = NULL;

    // Destroy
    IMGUI_DEBUG_LOG_VIEWPORT("[viewport] Delete Viewport %08X '%s'\n", viewport->ID, viewport->Window ? viewport->Window->Name : "n/a");
    DestroyPlatformWindow(viewport); // In most circumstances the platform window will already be destroyed here.
    IM_ASSERT(g.PlatformIO.Viewports.contains(viewport) == false);
    IM_ASSERT(g.Viewports[viewport->Idx] == viewport);
    g.Viewports.erase(g.Viewports.Data + viewport->Idx);
    IM_DELETE(viewport);
}

// FIXME-VIEWPORT: This is all super messy and ought to be clarified or rewritten.
static void ImGui::WindowSelectViewport(ImGuiWindow* window)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindowFlags flags = window->Flags;
    window->ViewportAllowPlatformMonitorExtend = -1;

    // Restore main viewport if multi-viewport is not supported by the backend
    ImGuiViewportP* main_viewport = (ImGuiViewportP*)(void*)GetMainViewport();
    if (!(g.ConfigFlagsCurrFrame & ImGuiConfigFlags_ViewportsEnable))
    {
        SetWindowViewport(window, main_viewport);
        return;
    }
    window->ViewportOwned = false;

    // Appearing popups reset their viewport so they can inherit again
    if ((flags & (ImGuiWindowFlags_Popup | ImGuiWindowFlags_Tooltip)) && window->Appearing)
    {
        window->Viewport = NULL;
        window->ViewportId = 0;
    }

    if ((g.NextWindowData.Flags & ImGuiNextWindowDataFlags_HasViewport) == 0)
    {
        // By default inherit from parent window
        if (window->Viewport == NULL && window->ParentWindow && (!window->ParentWindow->IsFallbackWindow || window->ParentWindow->WasActive))
            window->Viewport = window->ParentWindow->Viewport;

        // Attempt to restore saved viewport id (= window that hasn't been activated yet), try to restore the viewport based on saved 'window->ViewportPos' restored from .ini file
        if (window->Viewport == NULL && window->ViewportId != 0)
        {
            window->Viewport = (ImGuiViewportP*)FindViewportByID(window->ViewportId);
            if (window->Viewport == NULL && window->ViewportPos.x != FLT_MAX && window->ViewportPos.y != FLT_MAX)
                window->Viewport = AddUpdateViewport(window, window->ID, window->ViewportPos, window->Size, ImGuiViewportFlags_None);
        }
    }

    bool lock_viewport = false;
    if (g.NextWindowData.Flags & ImGuiNextWindowDataFlags_HasViewport)
    {
        // Code explicitly request a viewport
        window->Viewport = (ImGuiViewportP*)FindViewportByID(g.NextWindowData.ViewportId);
        window->ViewportId = g.NextWindowData.ViewportId; // Store ID even if Viewport isn't resolved yet.
        if (window->Viewport && (window->Flags & ImGuiWindowFlags_DockNodeHost) != 0 && window->Viewport->Window != NULL)
        {
            window->Viewport->Window = window;
            window->Viewport->ID = window->ViewportId = window->ID; // Overwrite ID (always owned by node)
        }
        lock_viewport = true;
    }
    else if ((flags & ImGuiWindowFlags_ChildWindow) || (flags & ImGuiWindowFlags_ChildMenu))
    {
        // Always inherit viewport from parent window
        if (window->DockNode && window->DockNode->HostWindow)
            IM_ASSERT(window->DockNode->HostWindow->Viewport == window->ParentWindow->Viewport);
        window->Viewport = window->ParentWindow->Viewport;
    }
    else if (window->DockNode && window->DockNode->HostWindow)
    {
        // This covers the "always inherit viewport from parent window" case for when a window reattach to a node that was just created mid-frame
        window->Viewport = window->DockNode->HostWindow->Viewport;
    }
    else if (flags & ImGuiWindowFlags_Tooltip)
    {
        window->Viewport = g.MouseViewport;
    }
    else if (GetWindowAlwaysWantOwnViewport(window))
    {
        window->Viewport = AddUpdateViewport(window, window->ID, window->Pos, window->Size, ImGuiViewportFlags_None);
    }
    else if (g.MovingWindow && g.MovingWindow->RootWindowDockTree == window && IsMousePosValid())
    {
        if (window->Viewport != NULL && window->Viewport->Window == window)
            window->Viewport = AddUpdateViewport(window, window->ID, window->Pos, window->Size, ImGuiViewportFlags_None);
    }
    else
    {
        // Merge into host viewport?
        // We cannot test window->ViewportOwned as it set lower in the function.
        // Testing (g.ActiveId == 0 || g.ActiveIdAllowOverlap) to avoid merging during a short-term widget interaction. Main intent was to avoid during resize (see #4212)
        bool try_to_merge_into_host_viewport = (window->Viewport && window == window->Viewport->Window && (g.ActiveId == 0 || g.ActiveIdAllowOverlap));
        if (try_to_merge_into_host_viewport)
            UpdateTryMergeWindowIntoHostViewports(window);
    }

    // Fallback: merge in default viewport if z-order matches, otherwise create a new viewport
    if (window->Viewport == NULL)
        if (!UpdateTryMergeWindowIntoHostViewport(window, main_viewport))
            window->Viewport = AddUpdateViewport(window, window->ID, window->Pos, window->Size, ImGuiViewportFlags_None);

    // Mark window as allowed to protrude outside of its viewport and into the current monitor
    if (!lock_viewport)
    {
        if (flags & (ImGuiWindowFlags_Tooltip | ImGuiWindowFlags_Popup))
        {
            // We need to take account of the possibility that mouse may become invalid.
            // Popups/Tooltip always set ViewportAllowPlatformMonitorExtend so GetWindowAllowedExtentRect() will return full monitor bounds.
            ImVec2 mouse_ref = (flags & ImGuiWindowFlags_Tooltip) ? g.IO.MousePos : g.BeginPopupStack.back().OpenMousePos;
            bool use_mouse_ref = (g.NavDisableHighlight || !g.NavDisableMouseHover || !g.NavWindow);
            bool mouse_valid = IsMousePosValid(&mouse_ref);
            if ((window->Appearing || (flags & (ImGuiWindowFlags_Tooltip | ImGuiWindowFlags_ChildMenu))) && (!use_mouse_ref || mouse_valid))
                window->ViewportAllowPlatformMonitorExtend = FindPlatformMonitorForPos((use_mouse_ref && mouse_valid) ? mouse_ref : NavCalcPreferredRefPos());
            else
                window->ViewportAllowPlatformMonitorExtend = window->Viewport->PlatformMonitor;
        }
        else if (window->Viewport && window != window->Viewport->Window && window->Viewport->Window && !(flags & ImGuiWindowFlags_ChildWindow) && window->DockNode == NULL)
        {
            // When called from Begin() we don't have access to a proper version of the Hidden flag yet, so we replicate this code.
            const bool will_be_visible = (window->DockIsActive && !window->DockTabIsVisible) ? false : true;
            if ((window->Flags & ImGuiWindowFlags_DockNodeHost) && window->Viewport->LastFrameActive < g.FrameCount && will_be_visible)
            {
                // Steal/transfer ownership
                IMGUI_DEBUG_LOG_VIEWPORT("[viewport] Window '%s' steal Viewport %08X from Window '%s'\n", window->Name, window->Viewport->ID, window->Viewport->Window->Name);
                window->Viewport->Window = window;
                window->Viewport->ID = window->ID;
                window->Viewport->LastNameHash = 0;
            }
            else if (!UpdateTryMergeWindowIntoHostViewports(window)) // Merge?
            {
                // New viewport
                window->Viewport = AddUpdateViewport(window, window->ID, window->Pos, window->Size, ImGuiViewportFlags_NoFocusOnAppearing);
            }
        }
        else if (window->ViewportAllowPlatformMonitorExtend < 0 && (flags & ImGuiWindowFlags_ChildWindow) == 0)
        {
            // Regular (non-child, non-popup) windows by default are also allowed to protrude
            // Child windows are kept contained within their parent.
            window->ViewportAllowPlatformMonitorExtend = window->Viewport->PlatformMonitor;
        }
    }

    // Update flags
    window->ViewportOwned = (window == window->Viewport->Window);
    window->ViewportId = window->Viewport->ID;

    // If the OS window has a title bar, hide our imgui title bar
    //if (window->ViewportOwned && !(window->Viewport->Flags & ImGuiViewportFlags_NoDecoration))
    //    window->Flags |= ImGuiWindowFlags_NoTitleBar;
}

void ImGui::WindowSyncOwnedViewport(ImGuiWindow* window, ImGuiWindow* parent_window_in_stack)
{
    ImGuiContext& g = *GImGui;

    bool viewport_rect_changed = false;

    // Synchronize window --> viewport in most situations
    // Synchronize viewport -> window in case the platform window has been moved or resized from the OS/WM
    if (window->Viewport->PlatformRequestMove)
    {
        window->Pos = window->Viewport->Pos;
        MarkIniSettingsDirty(window);
    }
    else if (memcmp(&window->Viewport->Pos, &window->Pos, sizeof(window->Pos)) != 0)
    {
        viewport_rect_changed = true;
        window->Viewport->Pos = window->Pos;
    }

    if (window->Viewport->PlatformRequestResize)
    {
        window->Size = window->SizeFull = window->Viewport->Size;
        MarkIniSettingsDirty(window);
    }
    else if (memcmp(&window->Viewport->Size, &window->Size, sizeof(window->Size)) != 0)
    {
        viewport_rect_changed = true;
        window->Viewport->Size = window->Size;
    }
    window->Viewport->UpdateWorkRect();

    // The viewport may have changed monitor since the global update in UpdateViewportsNewFrame()
    // Either a SetNextWindowPos() call in the current frame or a SetWindowPos() call in the previous frame may have this effect.
    if (viewport_rect_changed)
        UpdateViewportPlatformMonitor(window->Viewport);

    // Update common viewport flags
    const ImGuiViewportFlags viewport_flags_to_clear = ImGuiViewportFlags_TopMost | ImGuiViewportFlags_NoTaskBarIcon | ImGuiViewportFlags_NoDecoration | ImGuiViewportFlags_NoRendererClear;
    ImGuiViewportFlags viewport_flags = window->Viewport->Flags & ~viewport_flags_to_clear;
    ImGuiWindowFlags window_flags = window->Flags;
    const bool is_modal = (window_flags & ImGuiWindowFlags_Modal) != 0;
    const bool is_short_lived_floating_window = (window_flags & (ImGuiWindowFlags_ChildMenu | ImGuiWindowFlags_Tooltip | ImGuiWindowFlags_Popup)) != 0;
    if (window_flags & ImGuiWindowFlags_Tooltip)
        viewport_flags |= ImGuiViewportFlags_TopMost;
    if ((g.IO.ConfigViewportsNoTaskBarIcon || is_short_lived_floating_window) && !is_modal)
        viewport_flags |= ImGuiViewportFlags_NoTaskBarIcon;
    if (g.IO.ConfigViewportsNoDecoration || is_short_lived_floating_window)
        viewport_flags |= ImGuiViewportFlags_NoDecoration;

    // Not correct to set modal as topmost because:
    // - Because other popups can be stacked above a modal (e.g. combo box in a modal)
    // - ImGuiViewportFlags_TopMost is currently handled different in backends: in Win32 it is "appear top most" whereas in GLFW and SDL it is "stay topmost"
    //if (flags & ImGuiWindowFlags_Modal)
    //    viewport_flags |= ImGuiViewportFlags_TopMost;

    // For popups and menus that may be protruding out of their parent viewport, we enable _NoFocusOnClick so that clicking on them
    // won't steal the OS focus away from their parent window (which may be reflected in OS the title bar decoration).
    // Setting _NoFocusOnClick would technically prevent us from bringing back to front in case they are being covered by an OS window from a different app,
    // but it shouldn't be much of a problem considering those are already popups that are closed when clicking elsewhere.
    if (is_short_lived_floating_window && !is_modal)
        viewport_flags |= ImGuiViewportFlags_NoFocusOnAppearing | ImGuiViewportFlags_NoFocusOnClick;

    // We can overwrite viewport flags using ImGuiWindowClass (advanced users)
    if (window->WindowClass.ViewportFlagsOverrideSet)
        viewport_flags |= window->WindowClass.ViewportFlagsOverrideSet;
    if (window->WindowClass.ViewportFlagsOverrideClear)
        viewport_flags &= ~window->WindowClass.ViewportFlagsOverrideClear;

    // We can also tell the backend that clearing the platform window won't be necessary,
    // as our window background is filling the viewport and we have disabled BgAlpha.
    // FIXME: Work on support for per-viewport transparency (#2766)
    if (!(window_flags & ImGuiWindowFlags_NoBackground))
        viewport_flags |= ImGuiViewportFlags_NoRendererClear;

    window->Viewport->Flags = viewport_flags;

    // Update parent viewport ID
    // (the !IsFallbackWindow test mimic the one done in WindowSelectViewport())
    if (window->WindowClass.ParentViewportId != (ImGuiID)-1)
        window->Viewport->ParentViewportId = window->WindowClass.ParentViewportId;
    else if ((window_flags & (ImGuiWindowFlags_Popup | ImGuiWindowFlags_Tooltip)) && parent_window_in_stack && (!parent_window_in_stack->IsFallbackWindow || parent_window_in_stack->WasActive))
        window->Viewport->ParentViewportId = parent_window_in_stack->Viewport->ID;
    else
        window->Viewport->ParentViewportId = g.IO.ConfigViewportsNoDefaultParent ? 0 : IMGUI_VIEWPORT_DEFAULT_ID;
}

// Called by user at the end of the main loop, after EndFrame()
// This will handle the creation/update of all OS windows via function defined in the ImGuiPlatformIO api.
void ImGui::UpdatePlatformWindows()
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(g.FrameCountEnded == g.FrameCount && "Forgot to call Render() or EndFrame() before UpdatePlatformWindows()?");
    IM_ASSERT(g.FrameCountPlatformEnded < g.FrameCount);
    g.FrameCountPlatformEnded = g.FrameCount;
    if (!(g.ConfigFlagsCurrFrame & ImGuiConfigFlags_ViewportsEnable))
        return;

    // Create/resize/destroy platform windows to match each active viewport.
    // Skip the main viewport (index 0), which is always fully handled by the application!
    for (int i = 1; i < g.Viewports.Size; i++)
    {
        ImGuiViewportP* viewport = g.Viewports[i];

        // Destroy platform window if the viewport hasn't been submitted or if it is hosting a hidden window
        // (the implicit/fallback Debug##Default window will be registering its viewport then be disabled, causing a dummy DestroyPlatformWindow to be made each frame)
        bool destroy_platform_window = false;
        destroy_platform_window |= (viewport->LastFrameActive < g.FrameCount - 1);
        destroy_platform_window |= (viewport->Window && !IsWindowActiveAndVisible(viewport->Window));
        if (destroy_platform_window)
        {
            DestroyPlatformWindow(viewport);
            continue;
        }

        // New windows that appears directly in a new viewport won't always have a size on their first frame
        if (viewport->LastFrameActive < g.FrameCount || viewport->Size.x <= 0 || viewport->Size.y <= 0)
            continue;

        // Create window
        const bool is_new_platform_window = (viewport->PlatformWindowCreated == false);
        if (is_new_platform_window)
        {
            IMGUI_DEBUG_LOG_VIEWPORT("[viewport] Create Platform Window %08X '%s'\n", viewport->ID, viewport->Window ? viewport->Window->Name : "n/a");
            g.PlatformIO.Platform_CreateWindow(viewport);
            if (g.PlatformIO.Renderer_CreateWindow != NULL)
                g.PlatformIO.Renderer_CreateWindow(viewport);
            g.PlatformWindowsCreatedCount++;
            viewport->LastNameHash = 0;
            viewport->LastPlatformPos = viewport->LastPlatformSize = ImVec2(FLT_MAX, FLT_MAX); // By clearing those we'll enforce a call to Platform_SetWindowPos/Size below, before Platform_ShowWindow (FIXME: Is that necessary?)
            viewport->LastRendererSize = viewport->Size;                                       // We don't need to call Renderer_SetWindowSize() as it is expected Renderer_CreateWindow() already did it.
            viewport->PlatformWindowCreated = true;
        }

        // Apply Position and Size (from ImGui to Platform/Renderer backends)
        if ((viewport->LastPlatformPos.x != viewport->Pos.x || viewport->LastPlatformPos.y != viewport->Pos.y) && !viewport->PlatformRequestMove)
            g.PlatformIO.Platform_SetWindowPos(viewport, viewport->Pos);
        if ((viewport->LastPlatformSize.x != viewport->Size.x || viewport->LastPlatformSize.y != viewport->Size.y) && !viewport->PlatformRequestResize)
            g.PlatformIO.Platform_SetWindowSize(viewport, viewport->Size);
        if ((viewport->LastRendererSize.x != viewport->Size.x || viewport->LastRendererSize.y != viewport->Size.y) && g.PlatformIO.Renderer_SetWindowSize)
            g.PlatformIO.Renderer_SetWindowSize(viewport, viewport->Size);
        viewport->LastPlatformPos = viewport->Pos;
        viewport->LastPlatformSize = viewport->LastRendererSize = viewport->Size;

        // Update title bar (if it changed)
        if (ImGuiWindow* window_for_title = GetWindowForTitleDisplay(viewport->Window))
        {
            const char* title_begin = window_for_title->Name;
            char* title_end = (char*)(intptr_t)FindRenderedTextEnd(title_begin);
            const ImGuiID title_hash = ImHashStr(title_begin, title_end - title_begin);
            if (viewport->LastNameHash != title_hash)
            {
                char title_end_backup_c = *title_end;
                *title_end = 0; // Cut existing buffer short instead of doing an alloc/free, no small gain.
                g.PlatformIO.Platform_SetWindowTitle(viewport, title_begin);
                *title_end = title_end_backup_c;
                viewport->LastNameHash = title_hash;
            }
        }

        // Update alpha (if it changed)
        if (viewport->LastAlpha != viewport->Alpha && g.PlatformIO.Platform_SetWindowAlpha)
            g.PlatformIO.Platform_SetWindowAlpha(viewport, viewport->Alpha);
        viewport->LastAlpha = viewport->Alpha;

        // Optional, general purpose call to allow the backend to perform general book-keeping even if things haven't changed.
        if (g.PlatformIO.Platform_UpdateWindow)
            g.PlatformIO.Platform_UpdateWindow(viewport);

        if (is_new_platform_window)
        {
            // On startup ensure new platform window don't steal focus (give it a few frames, as nested contents may lead to viewport being created a few frames late)
            if (g.FrameCount < 3)
                viewport->Flags |= ImGuiViewportFlags_NoFocusOnAppearing;

            // Show window
            g.PlatformIO.Platform_ShowWindow(viewport);

            // Even without focus, we assume the window becomes front-most.
            // This is useful for our platform z-order heuristic when io.MouseHoveredViewport is not available.
            if (viewport->LastFocusedStampCount != g.ViewportFocusedStampCount)
                viewport->LastFocusedStampCount = ++g.ViewportFocusedStampCount;
        }

        // Clear request flags
        viewport->ClearRequestFlags();
    }
}

// This is a default/basic function for performing the rendering/swap of multiple Platform Windows.
// Custom renderers may prefer to not call this function at all, and instead iterate the publicly exposed platform data and handle rendering/sync themselves.
// The Render/Swap functions stored in ImGuiPlatformIO are merely here to allow for this helper to exist, but you can do it yourself:
//
//    ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
//    for (int i = 1; i < platform_io.Viewports.Size; i++)
//        if ((platform_io.Viewports[i]->Flags & ImGuiViewportFlags_Minimized) == 0)
//            MyRenderFunction(platform_io.Viewports[i], my_args);
//    for (int i = 1; i < platform_io.Viewports.Size; i++)
//        if ((platform_io.Viewports[i]->Flags & ImGuiViewportFlags_Minimized) == 0)
//            MySwapBufferFunction(platform_io.Viewports[i], my_args);
//
void ImGui::RenderPlatformWindowsDefault(void* platform_render_arg, void* renderer_render_arg)
{
    // Skip the main viewport (index 0), which is always fully handled by the application!
    ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
    for (int i = 1; i < platform_io.Viewports.Size; i++)
    {
        ImGuiViewport* viewport = platform_io.Viewports[i];
        if (viewport->Flags & ImGuiViewportFlags_IsMinimized)
            continue;
        if (platform_io.Platform_RenderWindow) platform_io.Platform_RenderWindow(viewport, platform_render_arg);
        if (platform_io.Renderer_RenderWindow) platform_io.Renderer_RenderWindow(viewport, renderer_render_arg);
    }
    for (int i = 1; i < platform_io.Viewports.Size; i++)
    {
        ImGuiViewport* viewport = platform_io.Viewports[i];
        if (viewport->Flags & ImGuiViewportFlags_IsMinimized)
            continue;
        if (platform_io.Platform_SwapBuffers) platform_io.Platform_SwapBuffers(viewport, platform_render_arg);
        if (platform_io.Renderer_SwapBuffers) platform_io.Renderer_SwapBuffers(viewport, renderer_render_arg);
    }
}

static int ImGui::FindPlatformMonitorForPos(const ImVec2& pos)
{
    ImGuiContext& g = *GImGui;
    for (int monitor_n = 0; monitor_n < g.PlatformIO.Monitors.Size; monitor_n++)
    {
        const ImGuiPlatformMonitor& monitor = g.PlatformIO.Monitors[monitor_n];
        if (ImRect(monitor.MainPos, monitor.MainPos + monitor.MainSize).Contains(pos))
            return monitor_n;
    }
    return -1;
}

// Search for the monitor with the largest intersection area with the given rectangle
// We generally try to avoid searching loops but the monitor count should be very small here
// FIXME-OPT: We could test the last monitor used for that viewport first, and early
static int ImGui::FindPlatformMonitorForRect(const ImRect& rect)
{
    ImGuiContext& g = *GImGui;

    const int monitor_count = g.PlatformIO.Monitors.Size;
    if (monitor_count <= 1)
        return monitor_count - 1;

    // Use a minimum threshold of 1.0f so a zero-sized rect won't false positive, and will still find the correct monitor given its position.
    // This is necessary for tooltips which always resize down to zero at first.
    const float surface_threshold = ImMax(rect.GetWidth() * rect.GetHeight() * 0.5f, 1.0f);
    int best_monitor_n = -1;
    float best_monitor_surface = 0.001f;

    for (int monitor_n = 0; monitor_n < g.PlatformIO.Monitors.Size && best_monitor_surface < surface_threshold; monitor_n++)
    {
        const ImGuiPlatformMonitor& monitor = g.PlatformIO.Monitors[monitor_n];
        const ImRect monitor_rect = ImRect(monitor.MainPos, monitor.MainPos + monitor.MainSize);
        if (monitor_rect.Contains(rect))
            return monitor_n;
        ImRect overlapping_rect = rect;
        overlapping_rect.ClipWithFull(monitor_rect);
        float overlapping_surface = overlapping_rect.GetWidth() * overlapping_rect.GetHeight();
        if (overlapping_surface < best_monitor_surface)
            continue;
        best_monitor_surface = overlapping_surface;
        best_monitor_n = monitor_n;
    }
    return best_monitor_n;
}

// Update monitor from viewport rectangle (we'll use this info to clamp windows and save windows lost in a removed monitor)
static void ImGui::UpdateViewportPlatformMonitor(ImGuiViewportP* viewport)
{
    viewport->PlatformMonitor = (short)FindPlatformMonitorForRect(viewport->GetMainRect());
}

// Return value is always != NULL, but don't hold on it across frames.
const ImGuiPlatformMonitor* ImGui::GetViewportPlatformMonitor(ImGuiViewport* viewport_p)
{
    ImGuiContext& g = *GImGui;
    ImGuiViewportP* viewport = (ImGuiViewportP*)(void*)viewport_p;
    int monitor_idx = viewport->PlatformMonitor;
    if (monitor_idx >= 0 && monitor_idx < g.PlatformIO.Monitors.Size)
        return &g.PlatformIO.Monitors[monitor_idx];
    return &g.FallbackMonitor;
}

void ImGui::DestroyPlatformWindow(ImGuiViewportP* viewport)
{
    ImGuiContext& g = *GImGui;
    if (viewport->PlatformWindowCreated)
    {
        IMGUI_DEBUG_LOG_VIEWPORT("[viewport] Destroy Platform Window %08X '%s'\n", viewport->ID, viewport->Window ? viewport->Window->Name : "n/a");
        if (g.PlatformIO.Renderer_DestroyWindow)
            g.PlatformIO.Renderer_DestroyWindow(viewport);
        if (g.PlatformIO.Platform_DestroyWindow)
            g.PlatformIO.Platform_DestroyWindow(viewport);
        IM_ASSERT(viewport->RendererUserData == NULL && viewport->PlatformUserData == NULL);

        // Don't clear PlatformWindowCreated for the main viewport, as we initially set that up to true in Initialize()
        // The righter way may be to leave it to the backend to set this flag all-together, and made the flag public.
        if (viewport->ID != IMGUI_VIEWPORT_DEFAULT_ID)
            viewport->PlatformWindowCreated = false;
    }
    else
    {
        IM_ASSERT(viewport->RendererUserData == NULL && viewport->PlatformUserData == NULL && viewport->PlatformHandle == NULL);
    }
    viewport->RendererUserData = viewport->PlatformUserData = viewport->PlatformHandle = NULL;
    viewport->ClearRequestFlags();
}

void ImGui::DestroyPlatformWindows()
{
    // We call the destroy window on every viewport (including the main viewport, index 0) to give a chance to the backend
    // to clear any data they may have stored in e.g. PlatformUserData, RendererUserData.
    // It is convenient for the platform backend code to store something in the main viewport, in order for e.g. the mouse handling
    // code to operator a consistent manner.
    // It is expected that the backend can handle calls to Renderer_DestroyWindow/Platform_DestroyWindow without
    // crashing if it doesn't have data stored.
    ImGuiContext& g = *GImGui;
    for (ImGuiViewportP* viewport : g.Viewports)
        DestroyPlatformWindow(viewport);
}


//-----------------------------------------------------------------------------
// [SECTION] DOCKING
//-----------------------------------------------------------------------------
// Docking: Internal Types
// Docking: Forward Declarations
// Docking: ImGuiDockContext
// Docking: ImGuiDockContext Docking/Undocking functions
// Docking: ImGuiDockNode
// Docking: ImGuiDockNode Tree manipulation functions
// Docking: Public Functions (SetWindowDock, DockSpace, DockSpaceOverViewport)
// Docking: Builder Functions
// Docking: Begin/End Support Functions (called from Begin/End)
// Docking: Settings
//-----------------------------------------------------------------------------

//-----------------------------------------------------------------------------
// Typical Docking call flow: (root level is generally public API):
//-----------------------------------------------------------------------------
// - NewFrame()                               new dear imgui frame
//    | DockContextNewFrameUpdateUndocking()  - process queued undocking requests
//    | - DockContextProcessUndockWindow()    - process one window undocking request
//    | - DockContextProcessUndockNode()      - process one whole node undocking request
//    | DockContextNewFrameUpdateUndocking()  - process queue docking requests, create floating dock nodes
//    | - update g.HoveredDockNode            - [debug] update node hovered by mouse
//    | - DockContextProcessDock()            - process one docking request
//    | - DockNodeUpdate()
//    |   - DockNodeUpdateForRootNode()
//    |     - DockNodeUpdateFlagsAndCollapse()
//    |     - DockNodeFindInfo()
//    |   - destroy unused node or tab bar
//    |   - create dock node host window
//    |      - Begin() etc.
//    |   - DockNodeStartMouseMovingWindow()
//    |   - DockNodeTreeUpdatePosSize()
//    |   - DockNodeTreeUpdateSplitter()
//    |   - draw node background
//    |   - DockNodeUpdateTabBar()            - create/update tab bar for a docking node
//    |     - DockNodeAddTabBar()
//    |     - DockNodeWindowMenuUpdate()
//    |     - DockNodeCalcTabBarLayout()
//    |     - BeginTabBarEx()
//    |     - TabItemEx() calls
//    |     - EndTabBar()
//    |   - BeginDockableDragDropTarget()
//    |      - DockNodeUpdate()               - recurse into child nodes...
//-----------------------------------------------------------------------------
// - DockSpace()                              user submit a dockspace into a window
//    | Begin(Child)                          - create a child window
//    | DockNodeUpdate()                      - call main dock node update function
//    | End(Child)
//    | ItemSize()
//-----------------------------------------------------------------------------
// - Begin()
//    | BeginDocked()
//    | BeginDockableDragDropSource()
//    | BeginDockableDragDropTarget()
//    | - DockNodePreviewDockRender()
//-----------------------------------------------------------------------------
// - EndFrame()
//    | DockContextEndFrame()
//-----------------------------------------------------------------------------

//-----------------------------------------------------------------------------
// Docking: Internal Types
//-----------------------------------------------------------------------------
// - ImGuiDockRequestType
// - ImGuiDockRequest
// - ImGuiDockPreviewData
// - ImGuiDockNodeSettings
// - ImGuiDockContext
//-----------------------------------------------------------------------------

enum ImGuiDockRequestType
{
    ImGuiDockRequestType_None = 0,
    ImGuiDockRequestType_Dock,
    ImGuiDockRequestType_Undock,
    ImGuiDockRequestType_Split                  // Split is the same as Dock but without a DockPayload
};

struct ImGuiDockRequest
{
    ImGuiDockRequestType    Type;
    ImGuiWindow*            DockTargetWindow;   // Destination/Target Window to dock into (may be a loose window or a DockNode, might be NULL in which case DockTargetNode cannot be NULL)
    ImGuiDockNode*          DockTargetNode;     // Destination/Target Node to dock into
    ImGuiWindow*            DockPayload;        // Source/Payload window to dock (may be a loose window or a DockNode), [Optional]
    ImGuiDir                DockSplitDir;
    float                   DockSplitRatio;
    bool                    DockSplitOuter;
    ImGuiWindow*            UndockTargetWindow;
    ImGuiDockNode*          UndockTargetNode;

    ImGuiDockRequest()
    {
        Type = ImGuiDockRequestType_None;
        DockTargetWindow = DockPayload = UndockTargetWindow = NULL;
        DockTargetNode = UndockTargetNode = NULL;
        DockSplitDir = ImGuiDir_None;
        DockSplitRatio = 0.5f;
        DockSplitOuter = false;
    }
};

struct ImGuiDockPreviewData
{
    ImGuiDockNode   FutureNode;
    bool            IsDropAllowed;
    bool            IsCenterAvailable;
    bool            IsSidesAvailable;           // Hold your breath, grammar freaks..
    bool            IsSplitDirExplicit;         // Set when hovered the drop rect (vs. implicit SplitDir==None when hovered the window)
    ImGuiDockNode*  SplitNode;
    ImGuiDir        SplitDir;
    float           SplitRatio;
    ImRect          DropRectsDraw[ImGuiDir_COUNT + 1];  // May be slightly different from hit-testing drop rects used in DockNodeCalcDropRects()

    ImGuiDockPreviewData() : FutureNode(0) { IsDropAllowed = IsCenterAvailable = IsSidesAvailable = IsSplitDirExplicit = false; SplitNode = NULL; SplitDir = ImGuiDir_None; SplitRatio = 0.f; for (int n = 0; n < IM_ARRAYSIZE(DropRectsDraw); n++) DropRectsDraw[n] = ImRect(+FLT_MAX, +FLT_MAX, -FLT_MAX, -FLT_MAX); }
};

// Persistent Settings data, stored contiguously in SettingsNodes (sizeof() ~32 bytes)
struct ImGuiDockNodeSettings
{
    ImGuiID             ID;
    ImGuiID             ParentNodeId;
    ImGuiID             ParentWindowId;
    ImGuiID             SelectedTabId;
    signed char         SplitAxis;
    char                Depth;
    ImGuiDockNodeFlags  Flags;                  // NB: We save individual flags one by one in ascii format (ImGuiDockNodeFlags_SavedFlagsMask_)
    ImVec2ih            Pos;
    ImVec2ih            Size;
    ImVec2ih            SizeRef;
    ImGuiDockNodeSettings() { memset(this, 0, sizeof(*this)); SplitAxis = ImGuiAxis_None; }
};

//-----------------------------------------------------------------------------
// Docking: Forward Declarations
//-----------------------------------------------------------------------------

namespace ImGui
{
    // ImGuiDockContext
    static ImGuiDockNode*   DockContextAddNode(ImGuiContext* ctx, ImGuiID id);
    static void             DockContextRemoveNode(ImGuiContext* ctx, ImGuiDockNode* node, bool merge_sibling_into_parent_node);
    static void             DockContextQueueNotifyRemovedNode(ImGuiContext* ctx, ImGuiDockNode* node);
    static void             DockContextProcessDock(ImGuiContext* ctx, ImGuiDockRequest* req);
    static void             DockContextPruneUnusedSettingsNodes(ImGuiContext* ctx);
    static ImGuiDockNode*   DockContextBindNodeToWindow(ImGuiContext* ctx, ImGuiWindow* window);
    static void             DockContextBuildNodesFromSettings(ImGuiContext* ctx, ImGuiDockNodeSettings* node_settings_array, int node_settings_count);
    static void             DockContextBuildAddWindowsToNodes(ImGuiContext* ctx, ImGuiID root_id);                            // Use root_id==0 to add all

    // ImGuiDockNode
    static void             DockNodeAddWindow(ImGuiDockNode* node, ImGuiWindow* window, bool add_to_tab_bar);
    static void             DockNodeMoveWindows(ImGuiDockNode* dst_node, ImGuiDockNode* src_node);
    static void             DockNodeMoveChildNodes(ImGuiDockNode* dst_node, ImGuiDockNode* src_node);
    static ImGuiWindow*     DockNodeFindWindowByID(ImGuiDockNode* node, ImGuiID id);
    static void             DockNodeApplyPosSizeToWindows(ImGuiDockNode* node);
    static void             DockNodeRemoveWindow(ImGuiDockNode* node, ImGuiWindow* window, ImGuiID save_dock_id);
    static void             DockNodeHideHostWindow(ImGuiDockNode* node);
    static void             DockNodeUpdate(ImGuiDockNode* node);
    static void             DockNodeUpdateForRootNode(ImGuiDockNode* node);
    static void             DockNodeUpdateFlagsAndCollapse(ImGuiDockNode* node);
    static void             DockNodeUpdateHasCentralNodeChild(ImGuiDockNode* node);
    static void             DockNodeUpdateTabBar(ImGuiDockNode* node, ImGuiWindow* host_window);
    static void             DockNodeAddTabBar(ImGuiDockNode* node);
    static void             DockNodeRemoveTabBar(ImGuiDockNode* node);
    static void             DockNodeWindowMenuUpdate(ImGuiDockNode* node, ImGuiTabBar* tab_bar);
    static void             DockNodeUpdateVisibleFlag(ImGuiDockNode* node);
    static void             DockNodeStartMouseMovingWindow(ImGuiDockNode* node, ImGuiWindow* window);
    static bool             DockNodeIsDropAllowed(ImGuiWindow* host_window, ImGuiWindow* payload_window);
    static void             DockNodePreviewDockSetup(ImGuiWindow* host_window, ImGuiDockNode* host_node, ImGuiWindow* payload_window, ImGuiDockNode* payload_node, ImGuiDockPreviewData* preview_data, bool is_explicit_target, bool is_outer_docking);
    static void             DockNodePreviewDockRender(ImGuiWindow* host_window, ImGuiDockNode* host_node, ImGuiWindow* payload_window, const ImGuiDockPreviewData* preview_data);
    static void             DockNodeCalcTabBarLayout(const ImGuiDockNode* node, ImRect* out_title_rect, ImRect* out_tab_bar_rect, ImVec2* out_window_menu_button_pos, ImVec2* out_close_button_pos);
    static void             DockNodeCalcSplitRects(ImVec2& pos_old, ImVec2& size_old, ImVec2& pos_new, ImVec2& size_new, ImGuiDir dir, ImVec2 size_new_desired);
    static bool             DockNodeCalcDropRectsAndTestMousePos(const ImRect& parent, ImGuiDir dir, ImRect& out_draw, bool outer_docking, ImVec2* test_mouse_pos);
    static const char*      DockNodeGetHostWindowTitle(ImGuiDockNode* node, char* buf, int buf_size) { ImFormatString(buf, buf_size, "##DockNode_%02X", node->ID); return buf; }
    static int              DockNodeGetTabOrder(ImGuiWindow* window);

    // ImGuiDockNode tree manipulations
    static void             DockNodeTreeSplit(ImGuiContext* ctx, ImGuiDockNode* parent_node, ImGuiAxis split_axis, int split_first_child, float split_ratio, ImGuiDockNode* new_node);
    static void             DockNodeTreeMerge(ImGuiContext* ctx, ImGuiDockNode* parent_node, ImGuiDockNode* merge_lead_child);
    static void             DockNodeTreeUpdatePosSize(ImGuiDockNode* node, ImVec2 pos, ImVec2 size, ImGuiDockNode* only_write_to_single_node = NULL);
    static void             DockNodeTreeUpdateSplitter(ImGuiDockNode* node);
    static ImGuiDockNode*   DockNodeTreeFindVisibleNodeByPos(ImGuiDockNode* node, ImVec2 pos);
    static ImGuiDockNode*   DockNodeTreeFindFallbackLeafNode(ImGuiDockNode* node);

    // Settings
    static void             DockSettingsRenameNodeReferences(ImGuiID old_node_id, ImGuiID new_node_id);
    static void             DockSettingsRemoveNodeReferences(ImGuiID* node_ids, int node_ids_count);
    static ImGuiDockNodeSettings*   DockSettingsFindNodeSettings(ImGuiContext* ctx, ImGuiID node_id);
    static void             DockSettingsHandler_ClearAll(ImGuiContext*, ImGuiSettingsHandler*);
    static void             DockSettingsHandler_ApplyAll(ImGuiContext*, ImGuiSettingsHandler*);
    static void*            DockSettingsHandler_ReadOpen(ImGuiContext*, ImGuiSettingsHandler*, const char* name);
    static void             DockSettingsHandler_ReadLine(ImGuiContext*, ImGuiSettingsHandler*, void* entry, const char* line);
    static void             DockSettingsHandler_WriteAll(ImGuiContext* imgui_ctx, ImGuiSettingsHandler* handler, ImGuiTextBuffer* buf);
}

//-----------------------------------------------------------------------------
// Docking: ImGuiDockContext
//-----------------------------------------------------------------------------
// The lifetime model is different from the one of regular windows: we always create a ImGuiDockNode for each ImGuiDockNodeSettings,
// or we always hold the entire docking node tree. Nodes are frequently hidden, e.g. if the window(s) or child nodes they host are not active.
// At boot time only, we run a simple GC to remove nodes that have no references.
// Because dock node settings (which are small, contiguous structures) are always mirrored by their corresponding dock nodes (more complete structures),
// we can also very easily recreate the nodes from scratch given the settings data (this is what DockContextRebuild() does).
// This is convenient as docking reconfiguration can be implemented by mostly poking at the simpler settings data.
//-----------------------------------------------------------------------------
// - DockContextInitialize()
// - DockContextShutdown()
// - DockContextClearNodes()
// - DockContextRebuildNodes()
// - DockContextNewFrameUpdateUndocking()
// - DockContextNewFrameUpdateDocking()
// - DockContextEndFrame()
// - DockContextFindNodeByID()
// - DockContextBindNodeToWindow()
// - DockContextGenNodeID()
// - DockContextAddNode()
// - DockContextRemoveNode()
// - ImGuiDockContextPruneNodeData
// - DockContextPruneUnusedSettingsNodes()
// - DockContextBuildNodesFromSettings()
// - DockContextBuildAddWindowsToNodes()
//-----------------------------------------------------------------------------

void ImGui::DockContextInitialize(ImGuiContext* ctx)
{
    ImGuiContext& g = *ctx;

    // Add .ini handle for persistent docking data
    ImGuiSettingsHandler ini_handler;
    ini_handler.TypeName = "Docking";
    ini_handler.TypeHash = ImHashStr("Docking");
    ini_handler.ClearAllFn = DockSettingsHandler_ClearAll;
    ini_handler.ReadInitFn = DockSettingsHandler_ClearAll; // Also clear on read
    ini_handler.ReadOpenFn = DockSettingsHandler_ReadOpen;
    ini_handler.ReadLineFn = DockSettingsHandler_ReadLine;
    ini_handler.ApplyAllFn = DockSettingsHandler_ApplyAll;
    ini_handler.WriteAllFn = DockSettingsHandler_WriteAll;
    g.SettingsHandlers.push_back(ini_handler);

    g.DockNodeWindowMenuHandler = &DockNodeWindowMenuHandler_Default;
}

void ImGui::DockContextShutdown(ImGuiContext* ctx)
{
    ImGuiDockContext* dc  = &ctx->DockContext;
    for (int n = 0; n < dc->Nodes.Data.Size; n++)
        if (ImGuiDockNode* node = (ImGuiDockNode*)dc->Nodes.Data[n].val_p)
            IM_DELETE(node);
}

void ImGui::DockContextClearNodes(ImGuiContext* ctx, ImGuiID root_id, bool clear_settings_refs)
{
    IM_UNUSED(ctx);
    IM_ASSERT(ctx == GImGui);
    DockBuilderRemoveNodeDockedWindows(root_id, clear_settings_refs);
    DockBuilderRemoveNodeChildNodes(root_id);
}

// [DEBUG] This function also acts as a defacto test to make sure we can rebuild from scratch without a glitch
// (Different from DockSettingsHandler_ClearAll() + DockSettingsHandler_ApplyAll() because this reuses current settings!)
void ImGui::DockContextRebuildNodes(ImGuiContext* ctx)
{
    ImGuiContext& g = *ctx;
    ImGuiDockContext* dc = &ctx->DockContext;
    IMGUI_DEBUG_LOG_DOCKING("[docking] DockContextRebuildNodes\n");
    SaveIniSettingsToMemory();
    ImGuiID root_id = 0; // Rebuild all
    DockContextClearNodes(ctx, root_id, false);
    DockContextBuildNodesFromSettings(ctx, dc->NodesSettings.Data, dc->NodesSettings.Size);
    DockContextBuildAddWindowsToNodes(ctx, root_id);
}

// Docking context update function, called by NewFrame()
void ImGui::DockContextNewFrameUpdateUndocking(ImGuiContext* ctx)
{
    ImGuiContext& g = *ctx;
    ImGuiDockContext* dc = &ctx->DockContext;
    if (!(g.IO.ConfigFlags & ImGuiConfigFlags_DockingEnable))
    {
        if (dc->Nodes.Data.Size > 0 || dc->Requests.Size > 0)
            DockContextClearNodes(ctx, 0, true);
        return;
    }

    // Setting NoSplit at runtime merges all nodes
    if (g.IO.ConfigDockingNoSplit)
        for (int n = 0; n < dc->Nodes.Data.Size; n++)
            if (ImGuiDockNode* node = (ImGuiDockNode*)dc->Nodes.Data[n].val_p)
                if (node->IsRootNode() && node->IsSplitNode())
                {
                    DockBuilderRemoveNodeChildNodes(node->ID);
                    //dc->WantFullRebuild = true;
                }

    // Process full rebuild
#if 0
    if (ImGui::IsKeyPressed(ImGui::GetKeyIndex(ImGuiKey_C)))
        dc->WantFullRebuild = true;
#endif
    if (dc->WantFullRebuild)
    {
        DockContextRebuildNodes(ctx);
        dc->WantFullRebuild = false;
    }

    // Process Undocking requests (we need to process them _before_ the UpdateMouseMovingWindowNewFrame call in NewFrame)
    for (ImGuiDockRequest& req : dc->Requests)
    {
        if (req.Type == ImGuiDockRequestType_Undock && req.UndockTargetWindow)
            DockContextProcessUndockWindow(ctx, req.UndockTargetWindow);
        else if (req.Type == ImGuiDockRequestType_Undock && req.UndockTargetNode)
            DockContextProcessUndockNode(ctx, req.UndockTargetNode);
    }
}

// Docking context update function, called by NewFrame()
void ImGui::DockContextNewFrameUpdateDocking(ImGuiContext* ctx)
{
    ImGuiContext& g = *ctx;
    ImGuiDockContext* dc  = &ctx->DockContext;
    if (!(g.IO.ConfigFlags & ImGuiConfigFlags_DockingEnable))
        return;

    // [DEBUG] Store hovered dock node.
    // We could in theory use DockNodeTreeFindVisibleNodeByPos() on the root host dock node, but using ->DockNode is a good shortcut.
    // Note this is mostly a debug thing and isn't actually used for docking target, because docking involve more detailed filtering.
    g.DebugHoveredDockNode = NULL;
    if (ImGuiWindow* hovered_window = g.HoveredWindowUnderMovingWindow)
    {
        if (hovered_window->DockNodeAsHost)
            g.DebugHoveredDockNode = DockNodeTreeFindVisibleNodeByPos(hovered_window->DockNodeAsHost, g.IO.MousePos);
        else if (hovered_window->RootWindow->DockNode)
            g.DebugHoveredDockNode = hovered_window->RootWindow->DockNode;
    }

    // Process Docking requests
    for (ImGuiDockRequest& req : dc->Requests)
        if (req.Type == ImGuiDockRequestType_Dock)
            DockContextProcessDock(ctx, &req);
    dc->Requests.resize(0);

    // Create windows for each automatic docking nodes
    // We can have NULL pointers when we delete nodes, but because ID are recycled this should amortize nicely (and our node count will never be very high)
    for (int n = 0; n < dc->Nodes.Data.Size; n++)
        if (ImGuiDockNode* node = (ImGuiDockNode*)dc->Nodes.Data[n].val_p)
            if (node->IsFloatingNode())
                DockNodeUpdate(node);
}

void ImGui::DockContextEndFrame(ImGuiContext* ctx)
{
    // Draw backgrounds of node missing their window
    ImGuiContext& g = *ctx;
    ImGuiDockContext* dc = &g.DockContext;
    for (int n = 0; n < dc->Nodes.Data.Size; n++)
        if (ImGuiDockNode* node = (ImGuiDockNode*)dc->Nodes.Data[n].val_p)
            if (node->LastFrameActive == g.FrameCount && node->IsVisible && node->HostWindow && node->IsLeafNode() && !node->IsBgDrawnThisFrame)
            {
                ImRect bg_rect(node->Pos + ImVec2(0.0f, GetFrameHeight()), node->Pos + node->Size);
                ImDrawFlags bg_rounding_flags = CalcRoundingFlagsForRectInRect(bg_rect, node->HostWindow->Rect(), g.Style.DockingSeparatorSize);
                node->HostWindow->DrawList->ChannelsSetCurrent(DOCKING_HOST_DRAW_CHANNEL_BG);
                node->HostWindow->DrawList->AddRectFilled(bg_rect.Min, bg_rect.Max, node->LastBgColor, node->HostWindow->WindowRounding, bg_rounding_flags);
            }
}

ImGuiDockNode* ImGui::DockContextFindNodeByID(ImGuiContext* ctx, ImGuiID id)
{
    return (ImGuiDockNode*)ctx->DockContext.Nodes.GetVoidPtr(id);
}

ImGuiID ImGui::DockContextGenNodeID(ImGuiContext* ctx)
{
    // Generate an ID for new node (the exact ID value doesn't matter as long as it is not already used)
    // FIXME-OPT FIXME-DOCK: This is suboptimal, even if the node count is small enough not to be a worry.0
    // We should poke in ctx->Nodes to find a suitable ID faster. Even more so trivial that ctx->Nodes lookup is already sorted.
    ImGuiID id = 0x0001;
    while (DockContextFindNodeByID(ctx, id) != NULL)
        id++;
    return id;
}

static ImGuiDockNode* ImGui::DockContextAddNode(ImGuiContext* ctx, ImGuiID id)
{
    // Generate an ID for the new node (the exact ID value doesn't matter as long as it is not already used) and add the first window.
    ImGuiContext& g = *ctx;
    if (id == 0)
        id = DockContextGenNodeID(ctx);
    else
        IM_ASSERT(DockContextFindNodeByID(ctx, id) == NULL);

    // We don't set node->LastFrameAlive on construction. Nodes are always created at all time to reflect .ini settings!
    IMGUI_DEBUG_LOG_DOCKING("[docking] DockContextAddNode 0x%08X\n", id);
    ImGuiDockNode* node = IM_NEW(ImGuiDockNode)(id);
    ctx->DockContext.Nodes.SetVoidPtr(node->ID, node);
    return node;
}

static void ImGui::DockContextRemoveNode(ImGuiContext* ctx, ImGuiDockNode* node, bool merge_sibling_into_parent_node)
{
    ImGuiContext& g = *ctx;
    ImGuiDockContext* dc  = &ctx->DockContext;

    IMGUI_DEBUG_LOG_DOCKING("[docking] DockContextRemoveNode 0x%08X\n", node->ID);
    IM_ASSERT(DockContextFindNodeByID(ctx, node->ID) == node);
    IM_ASSERT(node->ChildNodes[0] == NULL && node->ChildNodes[1] == NULL);
    IM_ASSERT(node->Windows.Size == 0);

    if (node->HostWindow)
        node->HostWindow->DockNodeAsHost = NULL;

    ImGuiDockNode* parent_node = node->ParentNode;
    const bool merge = (merge_sibling_into_parent_node && parent_node != NULL);
    if (merge)
    {
        IM_ASSERT(parent_node->ChildNodes[0] == node || parent_node->ChildNodes[1] == node);
        ImGuiDockNode* sibling_node = (parent_node->ChildNodes[0] == node ? parent_node->ChildNodes[1] : parent_node->ChildNodes[0]);
        DockNodeTreeMerge(&g, parent_node, sibling_node);
    }
    else
    {
        for (int n = 0; parent_node && n < IM_ARRAYSIZE(parent_node->ChildNodes); n++)
            if (parent_node->ChildNodes[n] == node)
                node->ParentNode->ChildNodes[n] = NULL;
        dc->Nodes.SetVoidPtr(node->ID, NULL);
        IM_DELETE(node);
    }
}

static int IMGUI_CDECL DockNodeComparerDepthMostFirst(const void* lhs, const void* rhs)
{
    const ImGuiDockNode* a = *(const ImGuiDockNode* const*)lhs;
    const ImGuiDockNode* b = *(const ImGuiDockNode* const*)rhs;
    return ImGui::DockNodeGetDepth(b) - ImGui::DockNodeGetDepth(a);
}

// Pre C++0x doesn't allow us to use a function-local type (without linkage) as template parameter, so we moved this here.
struct ImGuiDockContextPruneNodeData
{
    int         CountWindows, CountChildWindows, CountChildNodes;
    ImGuiID     RootId;
    ImGuiDockContextPruneNodeData() { CountWindows = CountChildWindows = CountChildNodes = 0; RootId = 0; }
};

// Garbage collect unused nodes (run once at init time)
static void ImGui::DockContextPruneUnusedSettingsNodes(ImGuiContext* ctx)
{
    ImGuiContext& g = *ctx;
    ImGuiDockContext* dc  = &ctx->DockContext;
    IM_ASSERT(g.Windows.Size == 0);

    ImPool<ImGuiDockContextPruneNodeData> pool;
    pool.Reserve(dc->NodesSettings.Size);

    // Count child nodes and compute RootID
    for (int settings_n = 0; settings_n < dc->NodesSettings.Size; settings_n++)
    {
        ImGuiDockNodeSettings* settings = &dc->NodesSettings[settings_n];
        ImGuiDockContextPruneNodeData* parent_data = settings->ParentNodeId ? pool.GetByKey(settings->ParentNodeId) : 0;
        pool.GetOrAddByKey(settings->ID)->RootId = parent_data ? parent_data->RootId : settings->ID;
        if (settings->ParentNodeId)
            pool.GetOrAddByKey(settings->ParentNodeId)->CountChildNodes++;
    }

    // Count reference to dock ids from dockspaces
    // We track the 'auto-DockNode <- manual-Window <- manual-DockSpace' in order to avoid 'auto-DockNode' being ditched by DockContextPruneUnusedSettingsNodes()
    for (int settings_n = 0; settings_n < dc->NodesSettings.Size; settings_n++)
    {
        ImGuiDockNodeSettings* settings = &dc->NodesSettings[settings_n];
        if (settings->ParentWindowId != 0)
            if (ImGuiWindowSettings* window_settings = FindWindowSettingsByID(settings->ParentWindowId))
                if (window_settings->DockId)
                    if (ImGuiDockContextPruneNodeData* data = pool.GetByKey(window_settings->DockId))
                        data->CountChildNodes++;
    }

    // Count reference to dock ids from window settings
    // We guard against the possibility of an invalid .ini file (RootID may point to a missing node)
    for (ImGuiWindowSettings* settings = g.SettingsWindows.begin(); settings != NULL; settings = g.SettingsWindows.next_chunk(settings))
        if (ImGuiID dock_id = settings->DockId)
            if (ImGuiDockContextPruneNodeData* data = pool.GetByKey(dock_id))
            {
                data->CountWindows++;
                if (ImGuiDockContextPruneNodeData* data_root = (data->RootId == dock_id) ? data : pool.GetByKey(data->RootId))
                    data_root->CountChildWindows++;
            }

    // Prune
    for (int settings_n = 0; settings_n < dc->NodesSettings.Size; settings_n++)
    {
        ImGuiDockNodeSettings* settings = &dc->NodesSettings[settings_n];
        ImGuiDockContextPruneNodeData* data = pool.GetByKey(settings->ID);
        if (data->CountWindows > 1)
            continue;
        ImGuiDockContextPruneNodeData* data_root = (data->RootId == settings->ID) ? data : pool.GetByKey(data->RootId);

        bool remove = false;
        remove |= (data->CountWindows == 1 && settings->ParentNodeId == 0 && data->CountChildNodes == 0 && !(settings->Flags & ImGuiDockNodeFlags_CentralNode));  // Floating root node with only 1 window
        remove |= (data->CountWindows == 0 && settings->ParentNodeId == 0 && data->CountChildNodes == 0); // Leaf nodes with 0 window
        remove |= (data_root->CountChildWindows == 0);
        if (remove)
        {
            IMGUI_DEBUG_LOG_DOCKING("[docking] DockContextPruneUnusedSettingsNodes: Prune 0x%08X\n", settings->ID);
            DockSettingsRemoveNodeReferences(&settings->ID, 1);
            settings->ID = 0;
        }
    }
}

static void ImGui::DockContextBuildNodesFromSettings(ImGuiContext* ctx, ImGuiDockNodeSettings* node_settings_array, int node_settings_count)
{
    // Build nodes
    for (int node_n = 0; node_n < node_settings_count; node_n++)
    {
        ImGuiDockNodeSettings* settings = &node_settings_array[node_n];
        if (settings->ID == 0)
            continue;
        ImGuiDockNode* node = DockContextAddNode(ctx, settings->ID);
        node->ParentNode = settings->ParentNodeId ? DockContextFindNodeByID(ctx, settings->ParentNodeId) : NULL;
        node->Pos = ImVec2(settings->Pos.x, settings->Pos.y);
        node->Size = ImVec2(settings->Size.x, settings->Size.y);
        node->SizeRef = ImVec2(settings->SizeRef.x, settings->SizeRef.y);
        node->AuthorityForPos = node->AuthorityForSize = node->AuthorityForViewport = ImGuiDataAuthority_DockNode;
        if (node->ParentNode && node->ParentNode->ChildNodes[0] == NULL)
            node->ParentNode->ChildNodes[0] = node;
        else if (node->ParentNode && node->ParentNode->ChildNodes[1] == NULL)
            node->ParentNode->ChildNodes[1] = node;
        node->SelectedTabId = settings->SelectedTabId;
        node->SplitAxis = (ImGuiAxis)settings->SplitAxis;
        node->SetLocalFlags(settings->Flags & ImGuiDockNodeFlags_SavedFlagsMask_);

        // Bind host window immediately if it already exist (in case of a rebuild)
        // This is useful as the RootWindowForTitleBarHighlight links necessary to highlight the currently focused node requires node->HostWindow to be set.
        char host_window_title[20];
        ImGuiDockNode* root_node = DockNodeGetRootNode(node);
        node->HostWindow = FindWindowByName(DockNodeGetHostWindowTitle(root_node, host_window_title, IM_ARRAYSIZE(host_window_title)));
    }
}

void ImGui::DockContextBuildAddWindowsToNodes(ImGuiContext* ctx, ImGuiID root_id)
{
    // Rebind all windows to nodes (they can also lazily rebind but we'll have a visible glitch during the first frame)
    ImGuiContext& g = *ctx;
    for (ImGuiWindow* window : g.Windows)
    {
        if (window->DockId == 0 || window->LastFrameActive < g.FrameCount - 1)
            continue;
        if (window->DockNode != NULL)
            continue;

        ImGuiDockNode* node = DockContextFindNodeByID(ctx, window->DockId);
        IM_ASSERT(node != NULL);   // This should have been called after DockContextBuildNodesFromSettings()
        if (root_id == 0 || DockNodeGetRootNode(node)->ID == root_id)
            DockNodeAddWindow(node, window, true);
    }
}

//-----------------------------------------------------------------------------
// Docking: ImGuiDockContext Docking/Undocking functions
//-----------------------------------------------------------------------------
// - DockContextQueueDock()
// - DockContextQueueUndockWindow()
// - DockContextQueueUndockNode()
// - DockContextQueueNotifyRemovedNode()
// - DockContextProcessDock()
// - DockContextProcessUndockWindow()
// - DockContextProcessUndockNode()
// - DockContextCalcDropPosForDocking()
//-----------------------------------------------------------------------------

void ImGui::DockContextQueueDock(ImGuiContext* ctx, ImGuiWindow* target, ImGuiDockNode* target_node, ImGuiWindow* payload, ImGuiDir split_dir, float split_ratio, bool split_outer)
{
    IM_ASSERT(target != payload);
    ImGuiDockRequest req;
    req.Type = ImGuiDockRequestType_Dock;
    req.DockTargetWindow = target;
    req.DockTargetNode = target_node;
    req.DockPayload = payload;
    req.DockSplitDir = split_dir;
    req.DockSplitRatio = split_ratio;
    req.DockSplitOuter = split_outer;
    ctx->DockContext.Requests.push_back(req);
}

void ImGui::DockContextQueueUndockWindow(ImGuiContext* ctx, ImGuiWindow* window)
{
    ImGuiDockRequest req;
    req.Type = ImGuiDockRequestType_Undock;
    req.UndockTargetWindow = window;
    ctx->DockContext.Requests.push_back(req);
}

void ImGui::DockContextQueueUndockNode(ImGuiContext* ctx, ImGuiDockNode* node)
{
    ImGuiDockRequest req;
    req.Type = ImGuiDockRequestType_Undock;
    req.UndockTargetNode = node;
    ctx->DockContext.Requests.push_back(req);
}

void ImGui::DockContextQueueNotifyRemovedNode(ImGuiContext* ctx, ImGuiDockNode* node)
{
    ImGuiDockContext* dc  = &ctx->DockContext;
    for (ImGuiDockRequest& req : dc->Requests)
        if (req.DockTargetNode == node)
            req.Type = ImGuiDockRequestType_None;
}

void ImGui::DockContextProcessDock(ImGuiContext* ctx, ImGuiDockRequest* req)
{
    IM_ASSERT((req->Type == ImGuiDockRequestType_Dock && req->DockPayload != NULL) || (req->Type == ImGuiDockRequestType_Split && req->DockPayload == NULL));
    IM_ASSERT(req->DockTargetWindow != NULL || req->DockTargetNode != NULL);

    ImGuiContext& g = *ctx;
    IM_UNUSED(g);

    ImGuiWindow* payload_window = req->DockPayload;     // Optional
    ImGuiWindow* target_window = req->DockTargetWindow;
    ImGuiDockNode* node = req->DockTargetNode;
    if (payload_window)
        IMGUI_DEBUG_LOG_DOCKING("[docking] DockContextProcessDock node 0x%08X target '%s' dock window '%s', split_dir %d\n", node ? node->ID : 0, target_window ? target_window->Name : "NULL", payload_window->Name, req->DockSplitDir);
    else
        IMGUI_DEBUG_LOG_DOCKING("[docking] DockContextProcessDock node 0x%08X, split_dir %d\n", node ? node->ID : 0, req->DockSplitDir);

    // Decide which Tab will be selected at the end of the operation
    ImGuiID next_selected_id = 0;
    ImGuiDockNode* payload_node = NULL;
    if (payload_window)
    {
        payload_node = payload_window->DockNodeAsHost;
        payload_window->DockNodeAsHost = NULL; // Important to clear this as the node will have its life as a child which might be merged/deleted later.
        if (payload_node && payload_node->IsLeafNode())
            next_selected_id = payload_node->TabBar->NextSelectedTabId ? payload_node->TabBar->NextSelectedTabId : payload_node->TabBar->SelectedTabId;
        if (payload_node == NULL)
            next_selected_id = payload_window->TabId;
    }

    // FIXME-DOCK: When we are trying to dock an existing single-window node into a loose window, transfer Node ID as well
    // When processing an interactive split, usually LastFrameAlive will be < g.FrameCount. But DockBuilder operations can make it ==.
    if (node)
        IM_ASSERT(node->LastFrameAlive <= g.FrameCount);
    if (node && target_window && node == target_window->DockNodeAsHost)
        IM_ASSERT(node->Windows.Size > 0 || node->IsSplitNode() || node->IsCentralNode());

    // Create new node and add existing window to it
    if (node == NULL)
    {
        node = DockContextAddNode(ctx, 0);
        node->Pos = target_window->Pos;
        node->Size = target_window->Size;
        if (target_window->DockNodeAsHost == NULL)
        {
            DockNodeAddWindow(node, target_window, true);
            node->TabBar->Tabs[0].Flags &= ~ImGuiTabItemFlags_Unsorted;
            target_window->DockIsActive = true;
        }
    }

    ImGuiDir split_dir = req->DockSplitDir;
    if (split_dir != ImGuiDir_None)
    {
        // Split into two, one side will be our payload node unless we are dropping a loose window
        const ImGuiAxis split_axis = (split_dir == ImGuiDir_Left || split_dir == ImGuiDir_Right) ? ImGuiAxis_X : ImGuiAxis_Y;
        const int split_inheritor_child_idx = (split_dir == ImGuiDir_Left || split_dir == ImGuiDir_Up) ? 1 : 0; // Current contents will be moved to the opposite side
        const float split_ratio = req->DockSplitRatio;
        DockNodeTreeSplit(ctx, node, split_axis, split_inheritor_child_idx, split_ratio, payload_node);  // payload_node may be NULL here!
        ImGuiDockNode* new_node = node->ChildNodes[split_inheritor_child_idx ^ 1];
        new_node->HostWindow = node->HostWindow;
        node = new_node;
    }
    node->SetLocalFlags(node->LocalFlags & ~ImGuiDockNodeFlags_HiddenTabBar);

    if (node != payload_node)
    {
        // Create tab bar before we call DockNodeMoveWindows (which would attempt to move the old tab-bar, which would lead us to payload tabs wrongly appearing before target tabs!)
        if (node->Windows.Size > 0 && node->TabBar == NULL)
        {
            DockNodeAddTabBar(node);
            for (int n = 0; n < node->Windows.Size; n++)
                TabBarAddTab(node->TabBar, ImGuiTabItemFlags_None, node->Windows[n]);
        }

        if (payload_node != NULL)
        {
            // Transfer full payload node (with 1+ child windows or child nodes)
            if (payload_node->IsSplitNode())
            {
                if (node->Windows.Size > 0)
                {
                    // We can dock a split payload into a node that already has windows _only_ if our payload is a node tree with a single visible node.
                    // In this situation, we move the windows of the target node into the currently visible node of the payload.
                    // This allows us to preserve some of the underlying dock tree settings nicely.
                    IM_ASSERT(payload_node->OnlyNodeWithWindows != NULL); // The docking should have been blocked by DockNodePreviewDockSetup() early on and never submitted.
                    ImGuiDockNode* visible_node = payload_node->OnlyNodeWithWindows;
                    if (visible_node->TabBar)
                        IM_ASSERT(visible_node->TabBar->Tabs.Size > 0);
                    DockNodeMoveWindows(node, visible_node);
                    DockNodeMoveWindows(visible_node, node);
                    DockSettingsRenameNodeReferences(node->ID, visible_node->ID);
                }
                if (node->IsCentralNode())
                {
                    // Central node property needs to be moved to a leaf node, pick the last focused one.
                    // FIXME-DOCK: If we had to transfer other flags here, what would the policy be?
                    ImGuiDockNode* last_focused_node = DockContextFindNodeByID(ctx, payload_node->LastFocusedNodeId);
                    IM_ASSERT(last_focused_node != NULL);
                    ImGuiDockNode* last_focused_root_node = DockNodeGetRootNode(last_focused_node);
                    IM_ASSERT(last_focused_root_node == DockNodeGetRootNode(payload_node));
                    last_focused_node->SetLocalFlags(last_focused_node->LocalFlags | ImGuiDockNodeFlags_CentralNode);
                    node->SetLocalFlags(node->LocalFlags & ~ImGuiDockNodeFlags_CentralNode);
                    last_focused_root_node->CentralNode = last_focused_node;
                }

                IM_ASSERT(node->Windows.Size == 0);
                DockNodeMoveChildNodes(node, payload_node);
            }
            else
            {
                const ImGuiID payload_dock_id = payload_node->ID;
                DockNodeMoveWindows(node, payload_node);
                DockSettingsRenameNodeReferences(payload_dock_id, node->ID);
            }
            DockContextRemoveNode(ctx, payload_node, true);
        }
        else if (payload_window)
        {
            // Transfer single window
            const ImGuiID payload_dock_id = payload_window->DockId;
            node->VisibleWindow = payload_window;
            DockNodeAddWindow(node, payload_window, true);
            if (payload_dock_id != 0)
                DockSettingsRenameNodeReferences(payload_dock_id, node->ID);
        }
    }
    else
    {
        // When docking a floating single window node we want to reevaluate auto-hiding of the tab bar
        node->WantHiddenTabBarUpdate = true;
    }

    // Update selection immediately
    if (ImGuiTabBar* tab_bar = node->TabBar)
        tab_bar->NextSelectedTabId = next_selected_id;
    MarkIniSettingsDirty();
}

// Problem:
//   Undocking a large (~full screen) window would leave it so large that the bottom right sizing corner would more
//   than likely be off the screen and the window would be hard to resize to fit on screen. This can be particularly problematic
//   with 'ConfigWindowsMoveFromTitleBarOnly=true' and/or with 'ConfigWindowsResizeFromEdges=false' as well (the later can be
//   due to missing ImGuiBackendFlags_HasMouseCursors backend flag).
// Solution:
//   When undocking a window we currently force its maximum size to 90% of the host viewport or monitor.
// Reevaluate this when we implement preserving docked/undocked size ("docking_wip/undocked_size" branch).
static ImVec2 FixLargeWindowsWhenUndocking(const ImVec2& size, ImGuiViewport* ref_viewport)
{
    if (ref_viewport == NULL)
        return size;

    ImGuiContext& g = *GImGui;
    ImVec2 max_size = ImTrunc(ref_viewport->WorkSize * 0.90f);
    if (g.ConfigFlagsCurrFrame & ImGuiConfigFlags_ViewportsEnable)
    {
        const ImGuiPlatformMonitor* monitor = ImGui::GetViewportPlatformMonitor(ref_viewport);
        max_size = ImTrunc(monitor->WorkSize * 0.90f);
    }
    return ImMin(size, max_size);
}

void ImGui::DockContextProcessUndockWindow(ImGuiContext* ctx, ImGuiWindow* window, bool clear_persistent_docking_ref)
{
    ImGuiContext& g = *ctx;
    IMGUI_DEBUG_LOG_DOCKING("[docking] DockContextProcessUndockWindow window '%s', clear_persistent_docking_ref = %d\n", window->Name, clear_persistent_docking_ref);
    if (window->DockNode)
        DockNodeRemoveWindow(window->DockNode, window, clear_persistent_docking_ref ? 0 : window->DockId);
    else
        window->DockId = 0;
    window->Collapsed = false;
    window->DockIsActive = false;
    window->DockNodeIsVisible = window->DockTabIsVisible = false;
    window->Size = window->SizeFull = FixLargeWindowsWhenUndocking(window->SizeFull, window->Viewport);

    MarkIniSettingsDirty();
}

void ImGui::DockContextProcessUndockNode(ImGuiContext* ctx, ImGuiDockNode* node)
{
    ImGuiContext& g = *ctx;
    IMGUI_DEBUG_LOG_DOCKING("[docking] DockContextProcessUndockNode node %08X\n", node->ID);
    IM_ASSERT(node->IsLeafNode());
    IM_ASSERT(node->Windows.Size >= 1);

    if (node->IsRootNode() || node->IsCentralNode())
    {
        // In the case of a root node or central node, the node will have to stay in place. Create a new node to receive the payload.
        ImGuiDockNode* new_node = DockContextAddNode(ctx, 0);
        new_node->Pos = node->Pos;
        new_node->Size = node->Size;
        new_node->SizeRef = node->SizeRef;
        DockNodeMoveWindows(new_node, node);
        DockSettingsRenameNodeReferences(node->ID, new_node->ID);
        node = new_node;
    }
    else
    {
        // Otherwise extract our node and merge our sibling back into the parent node.
        IM_ASSERT(node->ParentNode->ChildNodes[0] == node || node->ParentNode->ChildNodes[1] == node);
        int index_in_parent = (node->ParentNode->ChildNodes[0] == node) ? 0 : 1;
        node->ParentNode->ChildNodes[index_in_parent] = NULL;
        DockNodeTreeMerge(ctx, node->ParentNode, node->ParentNode->ChildNodes[index_in_parent ^ 1]);
        node->ParentNode->AuthorityForViewport = ImGuiDataAuthority_Window; // The node that stays in place keeps the viewport, so our newly dragged out node will create a new viewport
        node->ParentNode = NULL;
    }
    for (ImGuiWindow* window : node->Windows)
    {
        window->Flags &= ~ImGuiWindowFlags_ChildWindow;
        if (window->ParentWindow)
            window->ParentWindow->DC.ChildWindows.find_erase(window);
        UpdateWindowParentAndRootLinks(window, window->Flags, NULL);
    }
    node->AuthorityForPos = node->AuthorityForSize = ImGuiDataAuthority_DockNode;
    node->Size = FixLargeWindowsWhenUndocking(node->Size, node->Windows[0]->Viewport);
    node->WantMouseMove = true;
    MarkIniSettingsDirty();
}

// This is mostly used for automation.
bool ImGui::DockContextCalcDropPosForDocking(ImGuiWindow* target, ImGuiDockNode* target_node, ImGuiWindow* payload_window, ImGuiDockNode* payload_node, ImGuiDir split_dir, bool split_outer, ImVec2* out_pos)
{
    if (target != NULL && target_node == NULL)
        target_node = target->DockNode;

    // In DockNodePreviewDockSetup() for a root central node instead of showing both "inner" and "outer" drop rects
    // (which would be functionally identical) we only show the outer one. Reflect this here.
    if (target_node && target_node->ParentNode == NULL && target_node->IsCentralNode() && split_dir != ImGuiDir_None)
        split_outer = true;
    ImGuiDockPreviewData split_data;
    DockNodePreviewDockSetup(target, target_node, payload_window, payload_node, &split_data, false, split_outer);
    if (split_data.DropRectsDraw[split_dir+1].IsInverted())
        return false;
    *out_pos = split_data.DropRectsDraw[split_dir+1].GetCenter();
    return true;
}

//-----------------------------------------------------------------------------
// Docking: ImGuiDockNode
//-----------------------------------------------------------------------------
// - DockNodeGetTabOrder()
// - DockNodeAddWindow()
// - DockNodeRemoveWindow()
// - DockNodeMoveChildNodes()
// - DockNodeMoveWindows()
// - DockNodeApplyPosSizeToWindows()
// - DockNodeHideHostWindow()
// - ImGuiDockNodeFindInfoResults
// - DockNodeFindInfo()
// - DockNodeFindWindowByID()
// - DockNodeUpdateFlagsAndCollapse()
// - DockNodeUpdateHasCentralNodeFlag()
// - DockNodeUpdateVisibleFlag()
// - DockNodeStartMouseMovingWindow()
// - DockNodeUpdate()
// - DockNodeUpdateWindowMenu()
// - DockNodeBeginAmendTabBar()
// - DockNodeEndAmendTabBar()
// - DockNodeUpdateTabBar()
// - DockNodeAddTabBar()
// - DockNodeRemoveTabBar()
// - DockNodeIsDropAllowedOne()
// - DockNodeIsDropAllowed()
// - DockNodeCalcTabBarLayout()
// - DockNodeCalcSplitRects()
// - DockNodeCalcDropRectsAndTestMousePos()
// - DockNodePreviewDockSetup()
// - DockNodePreviewDockRender()
//-----------------------------------------------------------------------------

ImGuiDockNode::ImGuiDockNode(ImGuiID id)
{
    ID = id;
    SharedFlags = LocalFlags = LocalFlagsInWindows = MergedFlags = ImGuiDockNodeFlags_None;
    ParentNode = ChildNodes[0] = ChildNodes[1] = NULL;
    TabBar = NULL;
    SplitAxis = ImGuiAxis_None;

    State = ImGuiDockNodeState_Unknown;
    LastBgColor = IM_COL32_WHITE;
    HostWindow = VisibleWindow = NULL;
    CentralNode = OnlyNodeWithWindows = NULL;
    CountNodeWithWindows = 0;
    LastFrameAlive = LastFrameActive = LastFrameFocused = -1;
    LastFocusedNodeId = 0;
    SelectedTabId = 0;
    WantCloseTabId = 0;
    RefViewportId = 0;
    AuthorityForPos = AuthorityForSize = ImGuiDataAuthority_DockNode;
    AuthorityForViewport = ImGuiDataAuthority_Auto;
    IsVisible = true;
    IsFocused = HasCloseButton = HasWindowMenuButton = HasCentralNodeChild = false;
    IsBgDrawnThisFrame = false;
    WantCloseAll = WantLockSizeOnce = WantMouseMove = WantHiddenTabBarUpdate = WantHiddenTabBarToggle = false;
}

ImGuiDockNode::~ImGuiDockNode()
{
    IM_DELETE(TabBar);
    TabBar = NULL;
    ChildNodes[0] = ChildNodes[1] = NULL;
}

int ImGui::DockNodeGetTabOrder(ImGuiWindow* window)
{
    ImGuiTabBar* tab_bar = window->DockNode->TabBar;
    if (tab_bar == NULL)
        return -1;
    ImGuiTabItem* tab = TabBarFindTabByID(tab_bar, window->TabId);
    return tab ? TabBarGetTabOrder(tab_bar, tab) : -1;
}

static void DockNodeHideWindowDuringHostWindowCreation(ImGuiWindow* window)
{
    window->Hidden = true;
    window->HiddenFramesCanSkipItems = window->Active ? 1 : 2;
}

static void ImGui::DockNodeAddWindow(ImGuiDockNode* node, ImGuiWindow* window, bool add_to_tab_bar)
{
    ImGuiContext& g = *GImGui; (void)g;
    if (window->DockNode)
    {
        // Can overwrite an existing window->DockNode (e.g. pointing to a disabled DockSpace node)
        IM_ASSERT(window->DockNode->ID != node->ID);
        DockNodeRemoveWindow(window->DockNode, window, 0);
    }
    IM_ASSERT(window->DockNode == NULL || window->DockNodeAsHost == NULL);
    IMGUI_DEBUG_LOG_DOCKING("[docking] DockNodeAddWindow node 0x%08X window '%s'\n", node->ID, window->Name);

    // If more than 2 windows appeared on the same frame leading to the creation of a new hosting window,
    // we'll hide windows until the host window is ready. Hide the 1st window after its been output (so it is not visible for one frame).
    // We will call DockNodeHideWindowDuringHostWindowCreation() on ourselves in Begin()
    if (node->HostWindow == NULL && node->Windows.Size == 1 && node->Windows[0]->WasActive == false)
        DockNodeHideWindowDuringHostWindowCreation(node->Windows[0]);

    node->Windows.push_back(window);
    node->WantHiddenTabBarUpdate = true;
    window->DockNode = node;
    window->DockId = node->ID;
    window->DockIsActive = (node->Windows.Size > 1);
    window->DockTabWantClose = false;

    // When reactivating a node with one or two loose window, the window pos/size/viewport are authoritative over the node storage.
    // In particular it is important we init the viewport from the first window so we don't create two viewports and drop one.
    if (node->HostWindow == NULL && node->IsFloatingNode())
    {
        if (node->AuthorityForPos == ImGuiDataAuthority_Auto)
            node->AuthorityForPos = ImGuiDataAuthority_Window;
        if (node->AuthorityForSize == ImGuiDataAuthority_Auto)
            node->AuthorityForSize = ImGuiDataAuthority_Window;
        if (node->AuthorityForViewport == ImGuiDataAuthority_Auto)
            node->AuthorityForViewport = ImGuiDataAuthority_Window;
    }

    // Add to tab bar if requested
    if (add_to_tab_bar)
    {
        if (node->TabBar == NULL)
        {
            DockNodeAddTabBar(node);
            node->TabBar->SelectedTabId = node->TabBar->NextSelectedTabId = node->SelectedTabId;

            // Add existing windows
            for (int n = 0; n < node->Windows.Size - 1; n++)
                TabBarAddTab(node->TabBar, ImGuiTabItemFlags_None, node->Windows[n]);
        }
        TabBarAddTab(node->TabBar, ImGuiTabItemFlags_Unsorted, window);
    }

    DockNodeUpdateVisibleFlag(node);

    // Update this without waiting for the next time we Begin() in the window, so our host window will have the proper title bar color on its first frame.
    if (node->HostWindow)
        UpdateWindowParentAndRootLinks(window, window->Flags | ImGuiWindowFlags_ChildWindow, node->HostWindow);
}

static void ImGui::DockNodeRemoveWindow(ImGuiDockNode* node, ImGuiWindow* window, ImGuiID save_dock_id)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(window->DockNode == node);
    //IM_ASSERT(window->RootWindowDockTree == node->HostWindow);
    //IM_ASSERT(window->LastFrameActive < g.FrameCount);    // We may call this from Begin()
    IM_ASSERT(save_dock_id == 0 || save_dock_id == node->ID);
    IMGUI_DEBUG_LOG_DOCKING("[docking] DockNodeRemoveWindow node 0x%08X window '%s'\n", node->ID, window->Name);

    window->DockNode = NULL;
    window->DockIsActive = window->DockTabWantClose = false;
    window->DockId = save_dock_id;
    window->Flags &= ~ImGuiWindowFlags_ChildWindow;
    if (window->ParentWindow)
        window->ParentWindow->DC.ChildWindows.find_erase(window);
    UpdateWindowParentAndRootLinks(window, window->Flags, NULL); // Update immediately

    if (node->HostWindow && node->HostWindow->ViewportOwned)
    {
        // When undocking from a user interaction this will always run in NewFrame() and have not much effect.
        // But mid-frame, if we clear viewport we need to mark window as hidden as well.
        window->Viewport = NULL;
        window->ViewportId = 0;
        window->ViewportOwned = false;
        window->Hidden = true;
    }

    // Remove window
    bool erased = false;
    for (int n = 0; n < node->Windows.Size; n++)
        if (node->Windows[n] == window)
        {
            node->Windows.erase(node->Windows.Data + n);
            erased = true;
            break;
        }
    if (!erased)
        IM_ASSERT(erased);
    if (node->VisibleWindow == window)
        node->VisibleWindow = NULL;

    // Remove tab and possibly tab bar
    node->WantHiddenTabBarUpdate = true;
    if (node->TabBar)
    {
        TabBarRemoveTab(node->TabBar, window->TabId);
        const int tab_count_threshold_for_tab_bar = node->IsCentralNode() ? 1 : 2;
        if (node->Windows.Size < tab_count_threshold_for_tab_bar)
            DockNodeRemoveTabBar(node);
    }

    if (node->Windows.Size == 0 && !node->IsCentralNode() && !node->IsDockSpace() && window->DockId != node->ID)
    {
        // Automatic dock node delete themselves if they are not holding at least one tab
        DockContextRemoveNode(&g, node, true);
        return;
    }

    if (node->Windows.Size == 1 && !node->IsCentralNode() && node->HostWindow)
    {
        ImGuiWindow* remaining_window = node->Windows[0];
        // Note: we used to transport viewport ownership here.
        remaining_window->Collapsed = node->HostWindow->Collapsed;
    }

    // Update visibility immediately is required so the DockNodeUpdateRemoveInactiveChilds() processing can reflect changes up the tree
    DockNodeUpdateVisibleFlag(node);
}

static void ImGui::DockNodeMoveChildNodes(ImGuiDockNode* dst_node, ImGuiDockNode* src_node)
{
    IM_ASSERT(dst_node->Windows.Size == 0);
    dst_node->ChildNodes[0] = src_node->ChildNodes[0];
    dst_node->ChildNodes[1] = src_node->ChildNodes[1];
    if (dst_node->ChildNodes[0])
        dst_node->ChildNodes[0]->ParentNode = dst_node;
    if (dst_node->ChildNodes[1])
        dst_node->ChildNodes[1]->ParentNode = dst_node;
    dst_node->SplitAxis = src_node->SplitAxis;
    dst_node->SizeRef = src_node->SizeRef;
    src_node->ChildNodes[0] = src_node->ChildNodes[1] = NULL;
}

static void ImGui::DockNodeMoveWindows(ImGuiDockNode* dst_node, ImGuiDockNode* src_node)
{
    // Insert tabs in the same orders as currently ordered (node->Windows isn't ordered)
    IM_ASSERT(src_node && dst_node && dst_node != src_node);
    ImGuiTabBar* src_tab_bar = src_node->TabBar;
    if (src_tab_bar != NULL)
        IM_ASSERT(src_node->Windows.Size <= src_node->TabBar->Tabs.Size);

    // If the dst_node is empty we can just move the entire tab bar (to preserve selection, scrolling, etc.)
    bool move_tab_bar = (src_tab_bar != NULL) && (dst_node->TabBar == NULL);
    if (move_tab_bar)
    {
        dst_node->TabBar = src_node->TabBar;
        src_node->TabBar = NULL;
    }

    // Tab order is not important here, it is preserved by sorting in DockNodeUpdateTabBar().
    for (ImGuiWindow* window : src_node->Windows)
    {
        window->DockNode = NULL;
        window->DockIsActive = false;
        DockNodeAddWindow(dst_node, window, !move_tab_bar);
    }
    src_node->Windows.clear();

    if (!move_tab_bar && src_node->TabBar)
    {
        if (dst_node->TabBar)
            dst_node->TabBar->SelectedTabId = src_node->TabBar->SelectedTabId;
        DockNodeRemoveTabBar(src_node);
    }
}

static void ImGui::DockNodeApplyPosSizeToWindows(ImGuiDockNode* node)
{
    for (ImGuiWindow* window : node->Windows)
    {
        SetWindowPos(window, node->Pos, ImGuiCond_Always); // We don't assign directly to Pos because it can break the calculation of SizeContents on next frame
        SetWindowSize(window, node->Size, ImGuiCond_Always);
    }
}

static void ImGui::DockNodeHideHostWindow(ImGuiDockNode* node)
{
    if (node->HostWindow)
    {
        if (node->HostWindow->DockNodeAsHost == node)
            node->HostWindow->DockNodeAsHost = NULL;
        node->HostWindow = NULL;
    }

    if (node->Windows.Size == 1)
    {
        node->VisibleWindow = node->Windows[0];
        node->Windows[0]->DockIsActive = false;
    }

    if (node->TabBar)
        DockNodeRemoveTabBar(node);
}

// Search function called once by root node in DockNodeUpdate()
struct ImGuiDockNodeTreeInfo
{
    ImGuiDockNode*      CentralNode;
    ImGuiDockNode*      FirstNodeWithWindows;
    int                 CountNodesWithWindows;
    //ImGuiWindowClass  WindowClassForMerges;

    ImGuiDockNodeTreeInfo() { memset(this, 0, sizeof(*this)); }
};

static void DockNodeFindInfo(ImGuiDockNode* node, ImGuiDockNodeTreeInfo* info)
{
    if (node->Windows.Size > 0)
    {
        if (info->FirstNodeWithWindows == NULL)
            info->FirstNodeWithWindows = node;
        info->CountNodesWithWindows++;
    }
    if (node->IsCentralNode())
    {
        IM_ASSERT(info->CentralNode == NULL); // Should be only one
        IM_ASSERT(node->IsLeafNode() && "If you get this assert: please submit .ini file + repro of actions leading to this.");
        info->CentralNode = node;
    }
    if (info->CountNodesWithWindows > 1 && info->CentralNode != NULL)
        return;
    if (node->ChildNodes[0])
        DockNodeFindInfo(node->ChildNodes[0], info);
    if (node->ChildNodes[1])
        DockNodeFindInfo(node->ChildNodes[1], info);
}

static ImGuiWindow* ImGui::DockNodeFindWindowByID(ImGuiDockNode* node, ImGuiID id)
{
    IM_ASSERT(id != 0);
    for (ImGuiWindow* window : node->Windows)
        if (window->ID == id)
            return window;
    return NULL;
}

// - Remove inactive windows/nodes.
// - Update visibility flag.
static void ImGui::DockNodeUpdateFlagsAndCollapse(ImGuiDockNode* node)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(node->ParentNode == NULL || node->ParentNode->ChildNodes[0] == node || node->ParentNode->ChildNodes[1] == node);

    // Inherit most flags
    if (node->ParentNode)
        node->SharedFlags = node->ParentNode->SharedFlags & ImGuiDockNodeFlags_SharedFlagsInheritMask_;

    // Recurse into children
    // There is the possibility that one of our child becoming empty will delete itself and moving its sibling contents into 'node'.
    // If 'node->ChildNode[0]' delete itself, then 'node->ChildNode[1]->Windows' will be moved into 'node'
    // If 'node->ChildNode[1]' delete itself, then 'node->ChildNode[0]->Windows' will be moved into 'node' and the "remove inactive windows" loop will have run twice on those windows (harmless)
    node->HasCentralNodeChild = false;
    if (node->ChildNodes[0])
        DockNodeUpdateFlagsAndCollapse(node->ChildNodes[0]);
    if (node->ChildNodes[1])
        DockNodeUpdateFlagsAndCollapse(node->ChildNodes[1]);

    // Remove inactive windows, collapse nodes
    // Merge node flags overrides stored in windows
    node->LocalFlagsInWindows = ImGuiDockNodeFlags_None;
    for (int window_n = 0; window_n < node->Windows.Size; window_n++)
    {
        ImGuiWindow* window = node->Windows[window_n];
        IM_ASSERT(window->DockNode == node);

        bool node_was_active = (node->LastFrameActive + 1 == g.FrameCount);
        bool remove = false;
        remove |= node_was_active && (window->LastFrameActive + 1 < g.FrameCount);
        remove |= node_was_active && (node->WantCloseAll || node->WantCloseTabId == window->TabId) && window->HasCloseButton && !(window->Flags & ImGuiWindowFlags_UnsavedDocument);  // Submit all _expected_ closure from last frame
        remove |= (window->DockTabWantClose);
        if (remove)
        {
            window->DockTabWantClose = false;
            if (node->Windows.Size == 1 && !node->IsCentralNode())
            {
                DockNodeHideHostWindow(node);
                node->State = ImGuiDockNodeState_HostWindowHiddenBecauseSingleWindow;
                DockNodeRemoveWindow(node, window, node->ID); // Will delete the node so it'll be invalid on return
                return;
            }
            DockNodeRemoveWindow(node, window, node->ID);
            window_n--;
            continue;
        }

        // FIXME-DOCKING: Missing policies for conflict resolution, hence the "Experimental" tag on this.
        //node->LocalFlagsInWindow &= ~window->WindowClass.DockNodeFlagsOverrideClear;
        node->LocalFlagsInWindows |= window->WindowClass.DockNodeFlagsOverrideSet;
    }
    node->UpdateMergedFlags();

    // Auto-hide tab bar option
    ImGuiDockNodeFlags node_flags = node->MergedFlags;
    if (node->WantHiddenTabBarUpdate && node->Windows.Size == 1 && (node_flags & ImGuiDockNodeFlags_AutoHideTabBar) && !node->IsHiddenTabBar())
        node->WantHiddenTabBarToggle = true;
    node->WantHiddenTabBarUpdate = false;

    // Cancel toggling if we know our tab bar is enforced to be hidden at all times
    if (node->WantHiddenTabBarToggle && node->VisibleWindow && (node->VisibleWindow->WindowClass.DockNodeFlagsOverrideSet & ImGuiDockNodeFlags_HiddenTabBar))
        node->WantHiddenTabBarToggle = false;

    // Apply toggles at a single point of the frame (here!)
    if (node->Windows.Size > 1)
        node->SetLocalFlags(node->LocalFlags & ~ImGuiDockNodeFlags_HiddenTabBar);
    else if (node->WantHiddenTabBarToggle)
        node->SetLocalFlags(node->LocalFlags ^ ImGuiDockNodeFlags_HiddenTabBar);
    node->WantHiddenTabBarToggle = false;

    DockNodeUpdateVisibleFlag(node);
}

// This is rarely called as DockNodeUpdateForRootNode() generally does it most frames.
static void ImGui::DockNodeUpdateHasCentralNodeChild(ImGuiDockNode* node)
{
    node->HasCentralNodeChild = false;
    if (node->ChildNodes[0])
        DockNodeUpdateHasCentralNodeChild(node->ChildNodes[0]);
    if (node->ChildNodes[1])
        DockNodeUpdateHasCentralNodeChild(node->ChildNodes[1]);
    if (node->IsRootNode())
    {
        ImGuiDockNode* mark_node = node->CentralNode;
        while (mark_node)
        {
            mark_node->HasCentralNodeChild = true;
            mark_node = mark_node->ParentNode;
        }
    }
}

static void ImGui::DockNodeUpdateVisibleFlag(ImGuiDockNode* node)
{
    // Update visibility flag
    bool is_visible = (node->ParentNode == NULL) ? node->IsDockSpace() : node->IsCentralNode();
    is_visible |= (node->Windows.Size > 0);
    is_visible |= (node->ChildNodes[0] && node->ChildNodes[0]->IsVisible);
    is_visible |= (node->ChildNodes[1] && node->ChildNodes[1]->IsVisible);
    node->IsVisible = is_visible;
}

static void ImGui::DockNodeStartMouseMovingWindow(ImGuiDockNode* node, ImGuiWindow* window)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(node->WantMouseMove == true);
    StartMouseMovingWindow(window);
    g.ActiveIdClickOffset = g.IO.MouseClickedPos[0] - node->Pos;
    g.MovingWindow = window; // If we are docked into a non moveable root window, StartMouseMovingWindow() won't set g.MovingWindow. Override that decision.
    node->WantMouseMove = false;
}

// Update CentralNode, OnlyNodeWithWindows, LastFocusedNodeID. Copy window class.
static void ImGui::DockNodeUpdateForRootNode(ImGuiDockNode* node)
{
    DockNodeUpdateFlagsAndCollapse(node);

    // - Setup central node pointers
    // - Find if there's only a single visible window in the hierarchy (in which case we need to display a regular title bar -> FIXME-DOCK: that last part is not done yet!)
    // Cannot merge this with DockNodeUpdateFlagsAndCollapse() because FirstNodeWithWindows is found after window removal and child collapsing
    ImGuiDockNodeTreeInfo info;
    DockNodeFindInfo(node, &info);
    node->CentralNode = info.CentralNode;
    node->OnlyNodeWithWindows = (info.CountNodesWithWindows == 1) ? info.FirstNodeWithWindows : NULL;
    node->CountNodeWithWindows = info.CountNodesWithWindows;
    if (node->LastFocusedNodeId == 0 && info.FirstNodeWithWindows != NULL)
        node->LastFocusedNodeId = info.FirstNodeWithWindows->ID;

    // Copy the window class from of our first window so it can be used for proper dock filtering.
    // When node has mixed windows, prioritize the class with the most constraint (DockingAllowUnclassed = false) as the reference to copy.
    // FIXME-DOCK: We don't recurse properly, this code could be reworked to work from DockNodeUpdateScanRec.
    if (ImGuiDockNode* first_node_with_windows = info.FirstNodeWithWindows)
    {
        node->WindowClass = first_node_with_windows->Windows[0]->WindowClass;
        for (int n = 1; n < first_node_with_windows->Windows.Size; n++)
            if (first_node_with_windows->Windows[n]->WindowClass.DockingAllowUnclassed == false)
            {
                node->WindowClass = first_node_with_windows->Windows[n]->WindowClass;
                break;
            }
    }

    ImGuiDockNode* mark_node = node->CentralNode;
    while (mark_node)
    {
        mark_node->HasCentralNodeChild = true;
        mark_node = mark_node->ParentNode;
    }
}

static void DockNodeSetupHostWindow(ImGuiDockNode* node, ImGuiWindow* host_window)
{
    // Remove ourselves from any previous different host window
    // This can happen if a user mistakenly does (see #4295 for details):
    //  - N+0: DockBuilderAddNode(id, 0)    // missing ImGuiDockNodeFlags_DockSpace
    //  - N+1: NewFrame()                   // will create floating host window for that node
    //  - N+1: DockSpace(id)                // requalify node as dockspace, moving host window
    if (node->HostWindow && node->HostWindow != host_window && node->HostWindow->DockNodeAsHost == node)
        node->HostWindow->DockNodeAsHost = NULL;

    host_window->DockNodeAsHost = node;
    node->HostWindow = host_window;
}

static void ImGui::DockNodeUpdate(ImGuiDockNode* node)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(node->LastFrameActive != g.FrameCount);
    node->LastFrameAlive = g.FrameCount;
    node->IsBgDrawnThisFrame = false;

    node->CentralNode = node->OnlyNodeWithWindows = NULL;
    if (node->IsRootNode())
        DockNodeUpdateForRootNode(node);

    // Remove tab bar if not needed
    if (node->TabBar && node->IsNoTabBar())
        DockNodeRemoveTabBar(node);

    // Early out for hidden root dock nodes (when all DockId references are in inactive windows, or there is only 1 floating window holding on the DockId)
    bool want_to_hide_host_window = false;
    if (node->IsFloatingNode())
    {
        if (node->Windows.Size <= 1 && node->IsLeafNode())
            if (!g.IO.ConfigDockingAlwaysTabBar && (node->Windows.Size == 0 || !node->Windows[0]->WindowClass.DockingAlwaysTabBar))
                want_to_hide_host_window = true;
        if (node->CountNodeWithWindows == 0)
            want_to_hide_host_window = true;
    }
    if (want_to_hide_host_window)
    {
        if (node->Windows.Size == 1)
        {
            // Floating window pos/size is authoritative
            ImGuiWindow* single_window = node->Windows[0];
            node->Pos = single_window->Pos;
            node->Size = single_window->SizeFull;
            node->AuthorityForPos = node->AuthorityForSize = node->AuthorityForViewport = ImGuiDataAuthority_Window;

            // Transfer focus immediately so when we revert to a regular window it is immediately selected
            if (node->HostWindow && g.NavWindow == node->HostWindow)
                FocusWindow(single_window);
            if (node->HostWindow)
            {
                IMGUI_DEBUG_LOG_VIEWPORT("[viewport] Node %08X transfer Viewport %08X->%08X to Window '%s'\n", node->ID, node->HostWindow->Viewport->ID, single_window->ID, single_window->Name);
                single_window->Viewport = node->HostWindow->Viewport;
                single_window->ViewportId = node->HostWindow->ViewportId;
                if (node->HostWindow->ViewportOwned)
                {
                    single_window->Viewport->ID = single_window->ID;
                    single_window->Viewport->Window = single_window;
                    single_window->ViewportOwned = true;
                }
            }
            node->RefViewportId = single_window->ViewportId;
        }

        DockNodeHideHostWindow(node);
        node->State = ImGuiDockNodeState_HostWindowHiddenBecauseSingleWindow;
        node->WantCloseAll = false;
        node->WantCloseTabId = 0;
        node->HasCloseButton = node->HasWindowMenuButton = false;
        node->LastFrameActive = g.FrameCount;

        if (node->WantMouseMove && node->Windows.Size == 1)
            DockNodeStartMouseMovingWindow(node, node->Windows[0]);
        return;
    }

    // In some circumstance we will defer creating the host window (so everything will be kept hidden),
    // while the expected visible window is resizing itself.
    // This is important for first-time (no ini settings restored) single window when io.ConfigDockingAlwaysTabBar is enabled,
    // otherwise the node ends up using the minimum window size. Effectively those windows will take an extra frame to show up:
    //   N+0: Begin(): window created (with no known size), node is created
    //   N+1: DockNodeUpdate(): node skip creating host window / Begin(): window size applied, not visible
    //   N+2: DockNodeUpdate(): node can create host window / Begin(): window becomes visible
    // We could remove this frame if we could reliably calculate the expected window size during node update, before the Begin() code.
    // It would require a generalization of CalcWindowExpectedSize(), probably extracting code away from Begin().
    // In reality it isn't very important as user quickly ends up with size data in .ini file.
    if (node->IsVisible && node->HostWindow == NULL && node->IsFloatingNode() && node->IsLeafNode())
    {
        IM_ASSERT(node->Windows.Size > 0);
        ImGuiWindow* ref_window = NULL;
        if (node->SelectedTabId != 0) // Note that we prune single-window-node settings on .ini loading, so this is generally 0 for them!
            ref_window = DockNodeFindWindowByID(node, node->SelectedTabId);
        if (ref_window == NULL)
            ref_window = node->Windows[0];
        if (ref_window->AutoFitFramesX > 0 || ref_window->AutoFitFramesY > 0)
        {
            node->State = ImGuiDockNodeState_HostWindowHiddenBecauseWindowsAreResizing;
            return;
        }
    }

    const ImGuiDockNodeFlags node_flags = node->MergedFlags;

    // Decide if the node will have a close button and a window menu button
    node->HasWindowMenuButton = (node->Windows.Size > 0) && (node_flags & ImGuiDockNodeFlags_NoWindowMenuButton) == 0;
    node->HasCloseButton = false;
    for (ImGuiWindow* window : node->Windows)
    {
        // FIXME-DOCK: Setting DockIsActive here means that for single active window in a leaf node, DockIsActive will be cleared until the next Begin() call.
        node->HasCloseButton |= window->HasCloseButton;
        window->DockIsActive = (node->Windows.Size > 1);
    }
    if (node_flags & ImGuiDockNodeFlags_NoCloseButton)
        node->HasCloseButton = false;

    // Bind or create host window
    ImGuiWindow* host_window = NULL;
    bool beginned_into_host_window = false;
    if (node->IsDockSpace())
    {
        // [Explicit root dockspace node]
        IM_ASSERT(node->HostWindow);
        host_window = node->HostWindow;
    }
    else
    {
        // [Automatic root or child nodes]
        if (node->IsRootNode() && node->IsVisible)
        {
            ImGuiWindow* ref_window = (node->Windows.Size > 0) ? node->Windows[0] : NULL;

            // Sync Pos
            if (node->AuthorityForPos == ImGuiDataAuthority_Window && ref_window)
                SetNextWindowPos(ref_window->Pos);
            else if (node->AuthorityForPos == ImGuiDataAuthority_DockNode)
                SetNextWindowPos(node->Pos);

            // Sync Size
            if (node->AuthorityForSize == ImGuiDataAuthority_Window && ref_window)
                SetNextWindowSize(ref_window->SizeFull);
            else if (node->AuthorityForSize == ImGuiDataAuthority_DockNode)
                SetNextWindowSize(node->Size);

            // Sync Collapsed
            if (node->AuthorityForSize == ImGuiDataAuthority_Window && ref_window)
                SetNextWindowCollapsed(ref_window->Collapsed);

            // Sync Viewport
            if (node->AuthorityForViewport == ImGuiDataAuthority_Window && ref_window)
                SetNextWindowViewport(ref_window->ViewportId);
            else if (node->AuthorityForViewport == ImGuiDataAuthority_Window && node->RefViewportId != 0)
                SetNextWindowViewport(node->RefViewportId);

            SetNextWindowClass(&node->WindowClass);

            // Begin into the host window
            char window_label[20];
            DockNodeGetHostWindowTitle(node, window_label, IM_ARRAYSIZE(window_label));
            ImGuiWindowFlags window_flags = ImGuiWindowFlags_NoScrollbar | ImGuiWindowFlags_NoScrollWithMouse | ImGuiWindowFlags_DockNodeHost;
            window_flags |= ImGuiWindowFlags_NoFocusOnAppearing;
            window_flags |= ImGuiWindowFlags_NoSavedSettings | ImGuiWindowFlags_NoNavFocus | ImGuiWindowFlags_NoCollapse;
            window_flags |= ImGuiWindowFlags_NoTitleBar;

            SetNextWindowBgAlpha(0.0f); // Don't set ImGuiWindowFlags_NoBackground because it disables borders
            PushStyleVar(ImGuiStyleVar_WindowPadding, ImVec2(0, 0));
            Begin(window_label, NULL, window_flags);
            PopStyleVar();
            beginned_into_host_window = true;

            host_window = g.CurrentWindow;
            DockNodeSetupHostWindow(node, host_window);
            host_window->DC.CursorPos = host_window->Pos;
            node->Pos = host_window->Pos;
            node->Size = host_window->Size;

            // We set ImGuiWindowFlags_NoFocusOnAppearing because we don't want the host window to take full focus (e.g. steal NavWindow)
            // But we still it bring it to the front of display. There's no way to choose this precise behavior via window flags.
            // One simple case to ponder if: window A has a toggle to create windows B/C/D. Dock B/C/D together, clear the toggle and enable it again.
            // When reappearing B/C/D will request focus and be moved to the top of the display pile, but they are not linked to the dock host window
            // during the frame they appear. The dock host window would keep its old display order, and the sorting in EndFrame would move B/C/D back
            // after the dock host window, losing their top-most status.
            if (node->HostWindow->Appearing)
                BringWindowToDisplayFront(node->HostWindow);

            node->AuthorityForPos = node->AuthorityForSize = node->AuthorityForViewport = ImGuiDataAuthority_Auto;
        }
        else if (node->ParentNode)
        {
            node->HostWindow = host_window = node->ParentNode->HostWindow;
            node->AuthorityForPos = node->AuthorityForSize = node->AuthorityForViewport = ImGuiDataAuthority_Auto;
        }
        if (node->WantMouseMove && node->HostWindow)
            DockNodeStartMouseMovingWindow(node, node->HostWindow);
    }
    node->RefViewportId = 0; // Clear when we have a host window

    // Update focused node (the one whose title bar is highlight) within a node tree
    if (node->IsSplitNode())
        IM_ASSERT(node->TabBar == NULL);
    if (node->IsRootNode())
        if (ImGuiWindow* p_window = g.NavWindow ? g.NavWindow->RootWindow : NULL)
            while (p_window != NULL && p_window->DockNode != NULL)
            {
                ImGuiDockNode* p_node = DockNodeGetRootNode(p_window->DockNode);
                if (p_node == node)
                {
                    node->LastFocusedNodeId = p_window->DockNode->ID; // Note: not using root node ID!
                    break;
                }
                p_window = p_node->HostWindow ? p_node->HostWindow->RootWindow : NULL;
            }

    // Register a hit-test hole in the window unless we are currently dragging a window that is compatible with our dockspace
    ImGuiDockNode* central_node = node->CentralNode;
    const bool central_node_hole = node->IsRootNode() && host_window && (node_flags & ImGuiDockNodeFlags_PassthruCentralNode) != 0 && central_node != NULL && central_node->IsEmpty();
    bool central_node_hole_register_hit_test_hole = central_node_hole;
    if (central_node_hole)
        if (const ImGuiPayload* payload = ImGui::GetDragDropPayload())
            if (payload->IsDataType(IMGUI_PAYLOAD_TYPE_WINDOW) && DockNodeIsDropAllowed(host_window, *(ImGuiWindow**)payload->Data))
                central_node_hole_register_hit_test_hole = false;
    if (central_node_hole_register_hit_test_hole)
    {
        // We add a little padding to match the "resize from edges" behavior and allow grabbing the splitter easily.
        // (But we only add it if there's something else on the other side of the hole, otherwise for e.g. fullscreen
        // covering passthru node we'd have a gap on the edge not covered by the hole)
        IM_ASSERT(node->IsDockSpace()); // We cannot pass this flag without the DockSpace() api. Testing this because we also setup the hole in host_window->ParentNode
        ImGuiDockNode* root_node = DockNodeGetRootNode(central_node);
        ImRect root_rect(root_node->Pos, root_node->Pos + root_node->Size);
        ImRect hole_rect(central_node->Pos, central_node->Pos + central_node->Size);
        if (hole_rect.Min.x > root_rect.Min.x) { hole_rect.Min.x += WINDOWS_HOVER_PADDING; }
        if (hole_rect.Max.x < root_rect.Max.x) { hole_rect.Max.x -= WINDOWS_HOVER_PADDING; }
        if (hole_rect.Min.y > root_rect.Min.y) { hole_rect.Min.y += WINDOWS_HOVER_PADDING; }
        if (hole_rect.Max.y < root_rect.Max.y) { hole_rect.Max.y -= WINDOWS_HOVER_PADDING; }
        //GetForegroundDrawList()->AddRect(hole_rect.Min, hole_rect.Max, IM_COL32(255, 0, 0, 255));
        if (central_node_hole && !hole_rect.IsInverted())
        {
            SetWindowHitTestHole(host_window, hole_rect.Min, hole_rect.Max - hole_rect.Min);
            if (host_window->ParentWindow)
                SetWindowHitTestHole(host_window->ParentWindow, hole_rect.Min, hole_rect.Max - hole_rect.Min);
        }
    }

    // Update position/size, process and draw resizing splitters
    if (node->IsRootNode() && host_window)
    {
        DockNodeTreeUpdatePosSize(node, host_window->Pos, host_window->Size);
        PushStyleColor(ImGuiCol_Separator, g.Style.Colors[ImGuiCol_Border]);
        PushStyleColor(ImGuiCol_SeparatorActive, g.Style.Colors[ImGuiCol_ResizeGripActive]);
        PushStyleColor(ImGuiCol_SeparatorHovered, g.Style.Colors[ImGuiCol_ResizeGripHovered]);
        DockNodeTreeUpdateSplitter(node);
        PopStyleColor(3);
    }

    // Draw empty node background (currently can only be the Central Node)
    if (host_window && node->IsEmpty() && node->IsVisible)
    {
        host_window->DrawList->ChannelsSetCurrent(DOCKING_HOST_DRAW_CHANNEL_BG);
        node->LastBgColor = (node_flags & ImGuiDockNodeFlags_PassthruCentralNode) ? 0 : GetColorU32(ImGuiCol_DockingEmptyBg);
        if (node->LastBgColor != 0)
            host_window->DrawList->AddRectFilled(node->Pos, node->Pos + node->Size, node->LastBgColor);
        node->IsBgDrawnThisFrame = true;
    }

    // Draw whole dockspace background if ImGuiDockNodeFlags_PassthruCentralNode if set.
    // We need to draw a background at the root level if requested by ImGuiDockNodeFlags_PassthruCentralNode, but we will only know the correct pos/size
    // _after_ processing the resizing splitters. So we are using the DrawList channel splitting facility to submit drawing primitives out of order!
    const bool render_dockspace_bg = node->IsRootNode() && host_window && (node_flags & ImGuiDockNodeFlags_PassthruCentralNode) != 0;
    if (render_dockspace_bg && node->IsVisible)
    {
        host_window->DrawList->ChannelsSetCurrent(DOCKING_HOST_DRAW_CHANNEL_BG);
        if (central_node_hole)
            RenderRectFilledWithHole(host_window->DrawList, node->Rect(), central_node->Rect(), GetColorU32(ImGuiCol_WindowBg), 0.0f);
        else
            host_window->DrawList->AddRectFilled(node->Pos, node->Pos + node->Size, GetColorU32(ImGuiCol_WindowBg), 0.0f);
    }

    // Draw and populate Tab Bar
    if (host_window)
        host_window->DrawList->ChannelsSetCurrent(DOCKING_HOST_DRAW_CHANNEL_FG);
    if (host_window && node->Windows.Size > 0)
    {
        DockNodeUpdateTabBar(node, host_window);
    }
    else
    {
        node->WantCloseAll = false;
        node->WantCloseTabId = 0;
        node->IsFocused = false;
    }
    if (node->TabBar && node->TabBar->SelectedTabId)
        node->SelectedTabId = node->TabBar->SelectedTabId;
    else if (node->Windows.Size > 0)
        node->SelectedTabId = node->Windows[0]->TabId;

    // Draw payload drop target
    if (host_window && node->IsVisible)
        if (node->IsRootNode() && (g.MovingWindow == NULL || g.MovingWindow->RootWindowDockTree != host_window))
            BeginDockableDragDropTarget(host_window);

    // We update this after DockNodeUpdateTabBar()
    node->LastFrameActive = g.FrameCount;

    // Recurse into children
    // FIXME-DOCK FIXME-OPT: Should not need to recurse into children
    if (host_window)
    {
        if (node->ChildNodes[0])
            DockNodeUpdate(node->ChildNodes[0]);
        if (node->ChildNodes[1])
            DockNodeUpdate(node->ChildNodes[1]);

        // Render outer borders last (after the tab bar)
        if (node->IsRootNode())
            RenderWindowOuterBorders(host_window);
    }

    // End host window
    if (beginned_into_host_window) //-V1020
        End();
}

// Compare TabItem nodes given the last known DockOrder (will persist in .ini file as hint), used to sort tabs when multiple tabs are added on the same frame.
static int IMGUI_CDECL TabItemComparerByDockOrder(const void* lhs, const void* rhs)
{
    ImGuiWindow* a = ((const ImGuiTabItem*)lhs)->Window;
    ImGuiWindow* b = ((const ImGuiTabItem*)rhs)->Window;
    if (int d = ((a->DockOrder == -1) ? INT_MAX : a->DockOrder) - ((b->DockOrder == -1) ? INT_MAX : b->DockOrder))
        return d;
    return (a->BeginOrderWithinContext - b->BeginOrderWithinContext);
}

// Default handler for g.DockNodeWindowMenuHandler(): display the list of windows for a given dock-node.
// This is exceptionally stored in a function pointer to also user applications to tweak this menu (undocumented)
// Custom overrides may want to decorate, group, sort entries.
// Please note those are internal structures: if you copy this expect occasional breakage.
// (if you don't need to modify the "Tabs.Size == 1" behavior/path it is recommend you call this function in your handler)
void ImGui::DockNodeWindowMenuHandler_Default(ImGuiContext* ctx, ImGuiDockNode* node, ImGuiTabBar* tab_bar)
{
    IM_UNUSED(ctx);
    if (tab_bar->Tabs.Size == 1)
    {
        // "Hide tab bar" option. Being one of our rare user-facing string we pull it from a table.
        if (MenuItem(LocalizeGetMsg(ImGuiLocKey_DockingHideTabBar), NULL, node->IsHiddenTabBar()))
            node->WantHiddenTabBarToggle = true;
    }
    else
    {
        // Display a selectable list of windows in this docking node
        for (int tab_n = 0; tab_n < tab_bar->Tabs.Size; tab_n++)
        {
            ImGuiTabItem* tab = &tab_bar->Tabs[tab_n];
            if (tab->Flags & ImGuiTabItemFlags_Button)
                continue;
            if (Selectable(TabBarGetTabName(tab_bar, tab), tab->ID == tab_bar->SelectedTabId))
                TabBarQueueFocus(tab_bar, tab);
            SameLine();
            Text("   ");
        }
    }
}

static void ImGui::DockNodeWindowMenuUpdate(ImGuiDockNode* node, ImGuiTabBar* tab_bar)
{
    // Try to position the menu so it is more likely to stays within the same viewport
    ImGuiContext& g = *GImGui;
    if (g.Style.WindowMenuButtonPosition == ImGuiDir_Left)
        SetNextWindowPos(ImVec2(node->Pos.x, node->Pos.y + GetFrameHeight()), ImGuiCond_Always, ImVec2(0.0f, 0.0f));
    else
        SetNextWindowPos(ImVec2(node->Pos.x + node->Size.x, node->Pos.y + GetFrameHeight()), ImGuiCond_Always, ImVec2(1.0f, 0.0f));
    if (BeginPopup("#WindowMenu"))
    {
        node->IsFocused = true;
        g.DockNodeWindowMenuHandler(&g, node, tab_bar);
        EndPopup();
    }
}

// User helper to append/amend into a dock node tab bar. Most commonly used to add e.g. a "+" button.
bool ImGui::DockNodeBeginAmendTabBar(ImGuiDockNode* node)
{
    if (node->TabBar == NULL || node->HostWindow == NULL)
        return false;
    if (node->MergedFlags & ImGuiDockNodeFlags_KeepAliveOnly)
        return false;
    if (node->TabBar->ID == 0)
        return false;
    Begin(node->HostWindow->Name);
    PushOverrideID(node->ID);
    bool ret = BeginTabBarEx(node->TabBar, node->TabBar->BarRect, node->TabBar->Flags);
    IM_UNUSED(ret);
    IM_ASSERT(ret);
    return true;
}

void ImGui::DockNodeEndAmendTabBar()
{
    EndTabBar();
    PopID();
    End();
}

static bool IsDockNodeTitleBarHighlighted(ImGuiDockNode* node, ImGuiDockNode* root_node)
{
    // CTRL+Tab highlight (only highlighting leaf node, not whole hierarchy)
    ImGuiContext& g = *GImGui;
    if (g.NavWindowingTarget)
        return (g.NavWindowingTarget->DockNode == node);

    // FIXME-DOCKING: May want alternative to treat central node void differently? e.g. if (g.NavWindow == host_window)
    if (g.NavWindow && root_node->LastFocusedNodeId == node->ID)
    {
        // FIXME: This could all be backed in RootWindowForTitleBarHighlight? Probably need to reorganize for both dock nodes + other RootWindowForTitleBarHighlight users (not-node)
        ImGuiWindow* parent_window = g.NavWindow->RootWindow;
        while (parent_window->Flags & ImGuiWindowFlags_ChildMenu)
            parent_window = parent_window->ParentWindow->RootWindow;
        ImGuiDockNode* start_parent_node = parent_window->DockNodeAsHost ? parent_window->DockNodeAsHost : parent_window->DockNode;
        for (ImGuiDockNode* parent_node = start_parent_node; parent_node != NULL; parent_node = parent_node->HostWindow ? parent_node->HostWindow->RootWindow->DockNode : NULL)
            if ((parent_node = ImGui::DockNodeGetRootNode(parent_node)) == root_node)
                return true;
    }
    return false;
}

// Submit the tab bar corresponding to a dock node and various housekeeping details.
static void ImGui::DockNodeUpdateTabBar(ImGuiDockNode* node, ImGuiWindow* host_window)
{
    ImGuiContext& g = *GImGui;
    ImGuiStyle& style = g.Style;

    const bool node_was_active = (node->LastFrameActive + 1 == g.FrameCount);
    const bool closed_all = node->WantCloseAll && node_was_active;
    const ImGuiID closed_one = node->WantCloseTabId && node_was_active;
    node->WantCloseAll = false;
    node->WantCloseTabId = 0;

    // Decide if we should use a focused title bar color
    bool is_focused = false;
    ImGuiDockNode* root_node = DockNodeGetRootNode(node);
    if (IsDockNodeTitleBarHighlighted(node, root_node))
        is_focused = true;

    // Hidden tab bar will show a triangle on the upper-left (in Begin)
    if (node->IsHiddenTabBar() || node->IsNoTabBar())
    {
        node->VisibleWindow = (node->Windows.Size > 0) ? node->Windows[0] : NULL;
        node->IsFocused = is_focused;
        if (is_focused)
            node->LastFrameFocused = g.FrameCount;
        if (node->VisibleWindow)
        {
            // Notify root of visible window (used to display title in OS task bar)
            if (is_focused || root_node->VisibleWindow == NULL)
                root_node->VisibleWindow = node->VisibleWindow;
            if (node->TabBar)
                node->TabBar->VisibleTabId = node->VisibleWindow->TabId;
        }
        return;
    }

    // Move ourselves to the Menu layer (so we can be accessed by tapping Alt) + undo SkipItems flag in order to draw over the title bar even if the window is collapsed
    bool backup_skip_item = host_window->SkipItems;
    if (!node->IsDockSpace())
    {
        host_window->SkipItems = false;
        host_window->DC.NavLayerCurrent = ImGuiNavLayer_Menu;
    }

    // Use PushOverrideID() instead of PushID() to use the node id _without_ the host window ID.
    // This is to facilitate computing those ID from the outside, and will affect more or less only the ID of the collapse button, popup and tabs,
    // as docked windows themselves will override the stack with their own root ID.
    PushOverrideID(node->ID);
    ImGuiTabBar* tab_bar = node->TabBar;
    bool tab_bar_is_recreated = (tab_bar == NULL); // Tab bar are automatically destroyed when a node gets hidden
    if (tab_bar == NULL)
    {
        DockNodeAddTabBar(node);
        tab_bar = node->TabBar;
    }

    ImGuiID focus_tab_id = 0;
    node->IsFocused = is_focused;

    const ImGuiDockNodeFlags node_flags = node->MergedFlags;
    const bool has_window_menu_button = (node_flags & ImGuiDockNodeFlags_NoWindowMenuButton) == 0 && (style.WindowMenuButtonPosition != ImGuiDir_None);

    // In a dock node, the Collapse Button turns into the Window Menu button.
    // FIXME-DOCK FIXME-OPT: Could we recycle popups id across multiple dock nodes?
    if (has_window_menu_button && IsPopupOpen("#WindowMenu"))
    {
        ImGuiID next_selected_tab_id = tab_bar->NextSelectedTabId;
        DockNodeWindowMenuUpdate(node, tab_bar);
        if (tab_bar->NextSelectedTabId != 0 && tab_bar->NextSelectedTabId != next_selected_tab_id)
            focus_tab_id = tab_bar->NextSelectedTabId;
        is_focused |= node->IsFocused;
    }

    // Layout
    ImRect title_bar_rect, tab_bar_rect;
    ImVec2 window_menu_button_pos;
    ImVec2 close_button_pos;
    DockNodeCalcTabBarLayout(node, &title_bar_rect, &tab_bar_rect, &window_menu_button_pos, &close_button_pos);

    // Submit new tabs, they will be added as Unsorted and sorted below based on relative DockOrder value.
    const int tabs_count_old = tab_bar->Tabs.Size;
    for (int window_n = 0; window_n < node->Windows.Size; window_n++)
    {
        ImGuiWindow* window = node->Windows[window_n];
        if (TabBarFindTabByID(tab_bar, window->TabId) == NULL)
            TabBarAddTab(tab_bar, ImGuiTabItemFlags_Unsorted, window);
    }

    // Title bar
    if (is_focused)
        node->LastFrameFocused = g.FrameCount;
    ImU32 title_bar_col = GetColorU32(host_window->Collapsed ? ImGuiCol_TitleBgCollapsed : is_focused ? ImGuiCol_TitleBgActive : ImGuiCol_TitleBg);
    ImDrawFlags rounding_flags = CalcRoundingFlagsForRectInRect(title_bar_rect, host_window->Rect(), g.Style.DockingSeparatorSize);
    host_window->DrawList->AddRectFilled(title_bar_rect.Min, title_bar_rect.Max, title_bar_col, host_window->WindowRounding, rounding_flags);

    // Docking/Collapse button
    if (has_window_menu_button)
    {
        if (CollapseButton(host_window->GetID("#COLLAPSE"), window_menu_button_pos, node)) // == DockNodeGetWindowMenuButtonId(node)
            OpenPopup("#WindowMenu");
        if (IsItemActive())
            focus_tab_id = tab_bar->SelectedTabId;
        if (IsItemHovered(ImGuiHoveredFlags_ForTooltip | ImGuiHoveredFlags_DelayNormal) && g.HoveredIdTimer > 0.5f)
            SetTooltip("%s", LocalizeGetMsg(ImGuiLocKey_DockingDragToUndockOrMoveNode));
    }

    // If multiple tabs are appearing on the same frame, sort them based on their persistent DockOrder value
    int tabs_unsorted_start = tab_bar->Tabs.Size;
    for (int tab_n = tab_bar->Tabs.Size - 1; tab_n >= 0 && (tab_bar->Tabs[tab_n].Flags & ImGuiTabItemFlags_Unsorted); tab_n--)
    {
        // FIXME-DOCK: Consider only clearing the flag after the tab has been alive for a few consecutive frames, allowing late comers to not break sorting?
        tab_bar->Tabs[tab_n].Flags &= ~ImGuiTabItemFlags_Unsorted;
        tabs_unsorted_start = tab_n;
    }
    if (tab_bar->Tabs.Size > tabs_unsorted_start)
    {
        IMGUI_DEBUG_LOG_DOCKING("[docking] In node 0x%08X: %d new appearing tabs:%s\n", node->ID, tab_bar->Tabs.Size - tabs_unsorted_start, (tab_bar->Tabs.Size > tabs_unsorted_start + 1) ? " (will sort)" : "");
        for (int tab_n = tabs_unsorted_start; tab_n < tab_bar->Tabs.Size; tab_n++)
        {
            ImGuiTabItem* tab = &tab_bar->Tabs[tab_n];
            IMGUI_DEBUG_LOG_DOCKING("[docking] - Tab 0x%08X '%s' Order %d\n", tab->ID, TabBarGetTabName(tab_bar, tab), tab->Window ? tab->Window->DockOrder : -1);
        }
        IMGUI_DEBUG_LOG_DOCKING("[docking] SelectedTabId = 0x%08X, NavWindow->TabId = 0x%08X\n", node->SelectedTabId, g.NavWindow ? g.NavWindow->TabId : -1);
        if (tab_bar->Tabs.Size > tabs_unsorted_start + 1)
            ImQsort(tab_bar->Tabs.Data + tabs_unsorted_start, tab_bar->Tabs.Size - tabs_unsorted_start, sizeof(ImGuiTabItem), TabItemComparerByDockOrder);
    }

    // Apply NavWindow focus back to the tab bar
    if (g.NavWindow && g.NavWindow->RootWindow->DockNode == node)
        tab_bar->SelectedTabId = g.NavWindow->RootWindow->TabId;

    // Selected newly added tabs, or persistent tab ID if the tab bar was just recreated
    if (tab_bar_is_recreated && TabBarFindTabByID(tab_bar, node->SelectedTabId) != NULL)
        tab_bar->SelectedTabId = tab_bar->NextSelectedTabId = node->SelectedTabId;
    else if (tab_bar->Tabs.Size > tabs_count_old)
        tab_bar->SelectedTabId = tab_bar->NextSelectedTabId = tab_bar->Tabs.back().Window->TabId;

    // Begin tab bar
    ImGuiTabBarFlags tab_bar_flags = ImGuiTabBarFlags_Reorderable | ImGuiTabBarFlags_AutoSelectNewTabs; // | ImGuiTabBarFlags_NoTabListScrollingButtons);
    tab_bar_flags |= ImGuiTabBarFlags_SaveSettings | ImGuiTabBarFlags_DockNode;// | ImGuiTabBarFlags_FittingPolicyScroll;
    if (!host_window->Collapsed && is_focused)
        tab_bar_flags |= ImGuiTabBarFlags_IsFocused;
    tab_bar->ID = GetID("#TabBar");
    tab_bar->SeparatorMinX = node->Pos.x + host_window->WindowBorderSize; // Separator cover the whole node width
    tab_bar->SeparatorMaxX = node->Pos.x + node->Size.x - host_window->WindowBorderSize;
    BeginTabBarEx(tab_bar, tab_bar_rect, tab_bar_flags);
    //host_window->DrawList->AddRect(tab_bar_rect.Min, tab_bar_rect.Max, IM_COL32(255,0,255,255));

    // Backup style colors
    ImVec4 backup_style_cols[ImGuiWindowDockStyleCol_COUNT];
    for (int color_n = 0; color_n < ImGuiWindowDockStyleCol_COUNT; color_n++)
        backup_style_cols[color_n] = g.Style.Colors[GWindowDockStyleColors[color_n]];

    // Submit actual tabs
    node->VisibleWindow = NULL;
    for (int window_n = 0; window_n < node->Windows.Size; window_n++)
    {
        ImGuiWindow* window = node->Windows[window_n];
        if ((closed_all || closed_one == window->TabId) && window->HasCloseButton && !(window->Flags & ImGuiWindowFlags_UnsavedDocument))
            continue;
        if (window->LastFrameActive + 1 >= g.FrameCount || !node_was_active)
        {
            ImGuiTabItemFlags tab_item_flags = 0;
            tab_item_flags |= window->WindowClass.TabItemFlagsOverrideSet;
            if (window->Flags & ImGuiWindowFlags_UnsavedDocument)
                tab_item_flags |= ImGuiTabItemFlags_UnsavedDocument;
            if (tab_bar->Flags & ImGuiTabBarFlags_NoCloseWithMiddleMouseButton)
                tab_item_flags |= ImGuiTabItemFlags_NoCloseWithMiddleMouseButton;

            // Apply stored style overrides for the window
            for (int color_n = 0; color_n < ImGuiWindowDockStyleCol_COUNT; color_n++)
                g.Style.Colors[GWindowDockStyleColors[color_n]] = ColorConvertU32ToFloat4(window->DockStyle.Colors[color_n]);

            // Note that TabItemEx() calls TabBarCalcTabID() so our tab item ID will ignore the current ID stack (rightly so)
            bool tab_open = true;
            TabItemEx(tab_bar, window->Name, window->HasCloseButton ? &tab_open : NULL, tab_item_flags, window);
            if (!tab_open)
                node->WantCloseTabId = window->TabId;
            if (tab_bar->VisibleTabId == window->TabId)
                node->VisibleWindow = window;

            // Store last item data so it can be queried with IsItemXXX functions after the user Begin() call
            window->DockTabItemStatusFlags = g.LastItemData.StatusFlags;
            window->DockTabItemRect = g.LastItemData.Rect;

            // Update navigation ID on menu layer
            if (g.NavWindow && g.NavWindow->RootWindow == window && (window->DC.NavLayersActiveMask & (1 << ImGuiNavLayer_Menu)) == 0)
                host_window->NavLastIds[1] = window->TabId;
        }
    }

    // Restore style colors
    for (int color_n = 0; color_n < ImGuiWindowDockStyleCol_COUNT; color_n++)
        g.Style.Colors[GWindowDockStyleColors[color_n]] = backup_style_cols[color_n];

    // Notify root of visible window (used to display title in OS task bar)
    if (node->VisibleWindow)
        if (is_focused || root_node->VisibleWindow == NULL)
            root_node->VisibleWindow = node->VisibleWindow;

    // Close button (after VisibleWindow was updated)
    // Note that VisibleWindow may have been overrided by CTRL+Tabbing, so VisibleWindow->TabId may be != from tab_bar->SelectedTabId
    const bool close_button_is_enabled = node->HasCloseButton && node->VisibleWindow && node->VisibleWindow->HasCloseButton;
    const bool close_button_is_visible = node->HasCloseButton;
    //const bool close_button_is_visible = close_button_is_enabled; // Most people would expect this behavior of not even showing the button (leaving a hole since we can't claim that space as other windows in the tba bar have one)
    if (close_button_is_visible)
    {
        if (!close_button_is_enabled)
        {
            PushItemFlag(ImGuiItemFlags_Disabled, true);
            PushStyleColor(ImGuiCol_Text, style.Colors[ImGuiCol_Text] * ImVec4(1.0f,1.0f,1.0f,0.4f));
        }
        if (CloseButton(host_window->GetID("#CLOSE"), close_button_pos))
        {
            node->WantCloseAll = true;
            for (int n = 0; n < tab_bar->Tabs.Size; n++)
                TabBarCloseTab(tab_bar, &tab_bar->Tabs[n]);
        }
        //if (IsItemActive())
        //    focus_tab_id = tab_bar->SelectedTabId;
        if (!close_button_is_enabled)
        {
            PopStyleColor();
            PopItemFlag();
        }
    }

    // When clicking on the title bar outside of tabs, we still focus the selected tab for that node
    // FIXME: TabItems submitted earlier use AllowItemOverlap so we manually perform a more specific test for now (hovered || held) in order to not cover them.
    ImGuiID title_bar_id = host_window->GetID("#TITLEBAR");
    if (g.HoveredId == 0 || g.HoveredId == title_bar_id || g.ActiveId == title_bar_id)
    {
        // AllowOverlap mode required for appending into dock node tab bar,
        // otherwise dragging window will steal HoveredId and amended tabs cannot get them.
        bool held;
        KeepAliveID(title_bar_id);
        ButtonBehavior(title_bar_rect, title_bar_id, NULL, &held, ImGuiButtonFlags_AllowOverlap);
        if (g.HoveredId == title_bar_id)
        {
            g.LastItemData.ID = title_bar_id;
        }
        if (held)
        {
            if (IsMouseClicked(0))
                focus_tab_id = tab_bar->SelectedTabId;

            // Forward moving request to selected window
            if (ImGuiTabItem* tab = TabBarFindTabByID(tab_bar, tab_bar->SelectedTabId))
                StartMouseMovingWindowOrNode(tab->Window ? tab->Window : node->HostWindow, node, false); // Undock from tab bar empty space
        }
    }

    // Forward focus from host node to selected window
    //if (is_focused && g.NavWindow == host_window && !g.NavWindowingTarget)
    //    focus_tab_id = tab_bar->SelectedTabId;

    // When clicked on a tab we requested focus to the docked child
    // This overrides the value set by "forward focus from host node to selected window".
    if (tab_bar->NextSelectedTabId)
        focus_tab_id = tab_bar->NextSelectedTabId;

    // Apply navigation focus
    if (focus_tab_id != 0)
        if (ImGuiTabItem* tab = TabBarFindTabByID(tab_bar, focus_tab_id))
            if (tab->Window)
            {
                FocusWindow(tab->Window);
                NavInitWindow(tab->Window, false);
            }

    EndTabBar();
    PopID();

    // Restore SkipItems flag
    if (!node->IsDockSpace())
    {
        host_window->DC.NavLayerCurrent = ImGuiNavLayer_Main;
        host_window->SkipItems = backup_skip_item;
    }
}

static void ImGui::DockNodeAddTabBar(ImGuiDockNode* node)
{
    IM_ASSERT(node->TabBar == NULL);
    node->TabBar = IM_NEW(ImGuiTabBar);
}

static void ImGui::DockNodeRemoveTabBar(ImGuiDockNode* node)
{
    if (node->TabBar == NULL)
        return;
    IM_DELETE(node->TabBar);
    node->TabBar = NULL;
}

static bool DockNodeIsDropAllowedOne(ImGuiWindow* payload, ImGuiWindow* host_window)
{
    if (host_window->DockNodeAsHost && host_window->DockNodeAsHost->IsDockSpace() && payload->BeginOrderWithinContext < host_window->BeginOrderWithinContext)
        return false;

    ImGuiWindowClass* host_class = host_window->DockNodeAsHost ? &host_window->DockNodeAsHost->WindowClass : &host_window->WindowClass;
    ImGuiWindowClass* payload_class = &payload->WindowClass;
    if (host_class->ClassId != payload_class->ClassId)
    {
        bool pass = false;
        if (host_class->ClassId != 0 && host_class->DockingAllowUnclassed && payload_class->ClassId == 0)
            pass = true;
        if (payload_class->ClassId != 0 && payload_class->DockingAllowUnclassed && host_class->ClassId == 0)
            pass = true;
        if (!pass)
            return false;
    }

    // Prevent docking any window created above a popup
    // Technically we should support it (e.g. in the case of a long-lived modal window that had fancy docking features),
    // by e.g. adding a 'if (!ImGui::IsWindowWithinBeginStackOf(host_window, popup_window))' test.
    // But it would requires more work on our end because the dock host windows is technically created in NewFrame()
    // and our ->ParentXXX and ->RootXXX pointers inside windows are currently mislading or lacking.
    ImGuiContext& g = *GImGui;
    for (int i = g.OpenPopupStack.Size - 1; i >= 0; i--)
        if (ImGuiWindow* popup_window = g.OpenPopupStack[i].Window)
            if (ImGui::IsWindowWithinBeginStackOf(payload, popup_window))   // Payload is created from within a popup begin stack.
                return false;

    return true;
}

static bool ImGui::DockNodeIsDropAllowed(ImGuiWindow* host_window, ImGuiWindow* root_payload)
{
    if (root_payload->DockNodeAsHost && root_payload->DockNodeAsHost->IsSplitNode()) // FIXME-DOCK: Missing filtering
        return true;

    const int payload_count = root_payload->DockNodeAsHost ? root_payload->DockNodeAsHost->Windows.Size : 1;
    for (int payload_n = 0; payload_n < payload_count; payload_n++)
    {
        ImGuiWindow* payload = root_payload->DockNodeAsHost ? root_payload->DockNodeAsHost->Windows[payload_n] : root_payload;
        if (DockNodeIsDropAllowedOne(payload, host_window))
            return true;
    }
    return false;
}

// window menu button == collapse button when not in a dock node.
// FIXME: This is similar to RenderWindowTitleBarContents(), may want to share code.
static void ImGui::DockNodeCalcTabBarLayout(const ImGuiDockNode* node, ImRect* out_title_rect, ImRect* out_tab_bar_rect, ImVec2* out_window_menu_button_pos, ImVec2* out_close_button_pos)
{
    ImGuiContext& g = *GImGui;
    ImGuiStyle& style = g.Style;

    ImRect r = ImRect(node->Pos.x, node->Pos.y, node->Pos.x + node->Size.x, node->Pos.y + g.FontSize + g.Style.FramePadding.y * 2.0f);
    if (out_title_rect) { *out_title_rect = r; }

    r.Min.x += style.WindowBorderSize;
    r.Max.x -= style.WindowBorderSize;

    float button_sz = g.FontSize;
    r.Min.x += style.FramePadding.x;
    r.Max.x -= style.FramePadding.x;
    ImVec2 window_menu_button_pos = ImVec2(r.Min.x, r.Min.y + style.FramePadding.y);
    if (node->HasCloseButton)
    {
        if (out_close_button_pos) *out_close_button_pos = ImVec2(r.Max.x - button_sz, r.Min.y + style.FramePadding.y);
        r.Max.x -= button_sz + style.ItemInnerSpacing.x;
    }
    if (node->HasWindowMenuButton && style.WindowMenuButtonPosition == ImGuiDir_Left)
    {
        r.Min.x += button_sz + style.ItemInnerSpacing.x;
    }
    else if (node->HasWindowMenuButton && style.WindowMenuButtonPosition == ImGuiDir_Right)
    {
        window_menu_button_pos = ImVec2(r.Max.x - button_sz, r.Min.y + style.FramePadding.y);
        r.Max.x -= button_sz + style.ItemInnerSpacing.x;
    }
    if (out_tab_bar_rect) { *out_tab_bar_rect = r; }
    if (out_window_menu_button_pos) { *out_window_menu_button_pos = window_menu_button_pos; }
}

void ImGui::DockNodeCalcSplitRects(ImVec2& pos_old, ImVec2& size_old, ImVec2& pos_new, ImVec2& size_new, ImGuiDir dir, ImVec2 size_new_desired)
{
    ImGuiContext& g = *GImGui;
    const float dock_spacing = g.Style.ItemInnerSpacing.x;
    const ImGuiAxis axis = (dir == ImGuiDir_Left || dir == ImGuiDir_Right) ? ImGuiAxis_X : ImGuiAxis_Y;
    pos_new[axis ^ 1] = pos_old[axis ^ 1];
    size_new[axis ^ 1] = size_old[axis ^ 1];

    // Distribute size on given axis (with a desired size or equally)
    const float w_avail = size_old[axis] - dock_spacing;
    if (size_new_desired[axis] > 0.0f && size_new_desired[axis] <= w_avail * 0.5f)
    {
        size_new[axis] = size_new_desired[axis];
        size_old[axis] = IM_TRUNC(w_avail - size_new[axis]);
    }
    else
    {
        size_new[axis] = IM_TRUNC(w_avail * 0.5f);
        size_old[axis] = IM_TRUNC(w_avail - size_new[axis]);
    }

    // Position each node
    if (dir == ImGuiDir_Right || dir == ImGuiDir_Down)
    {
        pos_new[axis] = pos_old[axis] + size_old[axis] + dock_spacing;
    }
    else if (dir == ImGuiDir_Left || dir == ImGuiDir_Up)
    {
        pos_new[axis] = pos_old[axis];
        pos_old[axis] = pos_new[axis] + size_new[axis] + dock_spacing;
    }
}

// Retrieve the drop rectangles for a given direction or for the center + perform hit testing.
bool ImGui::DockNodeCalcDropRectsAndTestMousePos(const ImRect& parent, ImGuiDir dir, ImRect& out_r, bool outer_docking, ImVec2* test_mouse_pos)
{
    ImGuiContext& g = *GImGui;

    const float parent_smaller_axis = ImMin(parent.GetWidth(), parent.GetHeight());
    const float hs_for_central_nodes = ImMin(g.FontSize * 1.5f, ImMax(g.FontSize * 0.5f, parent_smaller_axis / 8.0f));
    float hs_w; // Half-size, longer axis
    float hs_h; // Half-size, smaller axis
    ImVec2 off; // Distance from edge or center
    if (outer_docking)
    {
        //hs_w = ImTrunc(ImClamp(parent_smaller_axis - hs_for_central_nodes * 4.0f, g.FontSize * 0.5f, g.FontSize * 8.0f));
        //hs_h = ImTrunc(hs_w * 0.15f);
        //off = ImVec2(ImTrunc(parent.GetWidth() * 0.5f - GetFrameHeightWithSpacing() * 1.4f - hs_h), ImTrunc(parent.GetHeight() * 0.5f - GetFrameHeightWithSpacing() * 1.4f - hs_h));
        hs_w = ImTrunc(hs_for_central_nodes * 1.50f);
        hs_h = ImTrunc(hs_for_central_nodes * 0.80f);
        off = ImTrunc(ImVec2(parent.GetWidth() * 0.5f - hs_h, parent.GetHeight() * 0.5f - hs_h));
    }
    else
    {
        hs_w = ImTrunc(hs_for_central_nodes);
        hs_h = ImTrunc(hs_for_central_nodes * 0.90f);
        off = ImTrunc(ImVec2(hs_w * 2.40f, hs_w * 2.40f));
    }

    ImVec2 c = ImTrunc(parent.GetCenter());
    if      (dir == ImGuiDir_None)  { out_r = ImRect(c.x - hs_w, c.y - hs_w,         c.x + hs_w, c.y + hs_w);         }
    else if (dir == ImGuiDir_Up)    { out_r = ImRect(c.x - hs_w, c.y - off.y - hs_h, c.x + hs_w, c.y - off.y + hs_h); }
    else if (dir == ImGuiDir_Down)  { out_r = ImRect(c.x - hs_w, c.y + off.y - hs_h, c.x + hs_w, c.y + off.y + hs_h); }
    else if (dir == ImGuiDir_Left)  { out_r = ImRect(c.x - off.x - hs_h, c.y - hs_w, c.x - off.x + hs_h, c.y + hs_w); }
    else if (dir == ImGuiDir_Right) { out_r = ImRect(c.x + off.x - hs_h, c.y - hs_w, c.x + off.x + hs_h, c.y + hs_w); }

    if (test_mouse_pos == NULL)
        return false;

    ImRect hit_r = out_r;
    if (!outer_docking)
    {
        // Custom hit testing for the 5-way selection, designed to reduce flickering when moving diagonally between sides
        hit_r.Expand(ImTrunc(hs_w * 0.30f));
        ImVec2 mouse_delta = (*test_mouse_pos - c);
        float mouse_delta_len2 = ImLengthSqr(mouse_delta);
        float r_threshold_center = hs_w * 1.4f;
        float r_threshold_sides = hs_w * (1.4f + 1.2f);
        if (mouse_delta_len2 < r_threshold_center * r_threshold_center)
            return (dir == ImGuiDir_None);
        if (mouse_delta_len2 < r_threshold_sides * r_threshold_sides)
            return (dir == ImGetDirQuadrantFromDelta(mouse_delta.x, mouse_delta.y));
    }
    return hit_r.Contains(*test_mouse_pos);
}

// host_node may be NULL if the window doesn't have a DockNode already.
// FIXME-DOCK: This is misnamed since it's also doing the filtering.
static void ImGui::DockNodePreviewDockSetup(ImGuiWindow* host_window, ImGuiDockNode* host_node, ImGuiWindow* payload_window, ImGuiDockNode* payload_node, ImGuiDockPreviewData* data, bool is_explicit_target, bool is_outer_docking)
{
    ImGuiContext& g = *GImGui;

    // There is an edge case when docking into a dockspace which only has inactive nodes.
    // In this case DockNodeTreeFindNodeByPos() will have selected a leaf node which is inactive.
    // Because the inactive leaf node doesn't have proper pos/size yet, we'll use the root node as reference.
    if (payload_node == NULL)
        payload_node = payload_window->DockNodeAsHost;
    ImGuiDockNode* ref_node_for_rect = (host_node && !host_node->IsVisible) ? DockNodeGetRootNode(host_node) : host_node;
    if (ref_node_for_rect)
        IM_ASSERT(ref_node_for_rect->IsVisible == true);

    // Filter, figure out where we are allowed to dock
    ImGuiDockNodeFlags src_node_flags = payload_node ? payload_node->MergedFlags : payload_window->WindowClass.DockNodeFlagsOverrideSet;
    ImGuiDockNodeFlags dst_node_flags = host_node ? host_node->MergedFlags : host_window->WindowClass.DockNodeFlagsOverrideSet;
    data->IsCenterAvailable = true;
    if (is_outer_docking)
        data->IsCenterAvailable = false;
    else if (dst_node_flags & ImGuiDockNodeFlags_NoDockingOverMe)
        data->IsCenterAvailable = false;
    else if (host_node && (dst_node_flags & ImGuiDockNodeFlags_NoDockingOverCentralNode) && host_node->IsCentralNode())
        data->IsCenterAvailable = false;
    else if ((!host_node || !host_node->IsEmpty()) && payload_node && payload_node->IsSplitNode() && (payload_node->OnlyNodeWithWindows == NULL)) // Is _visibly_ split?
        data->IsCenterAvailable = false;
    else if ((src_node_flags & ImGuiDockNodeFlags_NoDockingOverOther) && (!host_node || !host_node->IsEmpty()))
        data->IsCenterAvailable = false;
    else if ((src_node_flags & ImGuiDockNodeFlags_NoDockingOverEmpty) && host_node && host_node->IsEmpty())
        data->IsCenterAvailable = false;

    data->IsSidesAvailable = true;
    if ((dst_node_flags & ImGuiDockNodeFlags_NoDockingSplit) || g.IO.ConfigDockingNoSplit)
        data->IsSidesAvailable = false;
    else if (!is_outer_docking && host_node && host_node->ParentNode == NULL && host_node->IsCentralNode())
        data->IsSidesAvailable = false;
    else if (src_node_flags & ImGuiDockNodeFlags_NoDockingSplitOther)
        data->IsSidesAvailable = false;

    // Build a tentative future node (reuse same structure because it is practical. Shape will be readjusted when previewing a split)
    data->FutureNode.HasCloseButton = (host_node ? host_node->HasCloseButton : host_window->HasCloseButton) || (payload_window->HasCloseButton);
    data->FutureNode.HasWindowMenuButton = host_node ? true : ((host_window->Flags & ImGuiWindowFlags_NoCollapse) == 0);
    data->FutureNode.Pos = ref_node_for_rect ? ref_node_for_rect->Pos : host_window->Pos;
    data->FutureNode.Size = ref_node_for_rect ? ref_node_for_rect->Size : host_window->Size;

    // Calculate drop shapes geometry for allowed splitting directions
    IM_ASSERT(ImGuiDir_None == -1);
    data->SplitNode = host_node;
    data->SplitDir = ImGuiDir_None;
    data->IsSplitDirExplicit = false;
    if (!host_window->Collapsed)
        for (int dir = ImGuiDir_None; dir < ImGuiDir_COUNT; dir++)
        {
            if (dir == ImGuiDir_None && !data->IsCenterAvailable)
                continue;
            if (dir != ImGuiDir_None && !data->IsSidesAvailable)
                continue;
            if (DockNodeCalcDropRectsAndTestMousePos(data->FutureNode.Rect(), (ImGuiDir)dir, data->DropRectsDraw[dir+1], is_outer_docking, &g.IO.MousePos))
            {
                data->SplitDir = (ImGuiDir)dir;
                data->IsSplitDirExplicit = true;
            }
        }

    // When docking without holding Shift, we only allow and preview docking when hovering over a drop rect or over the title bar
    data->IsDropAllowed = (data->SplitDir != ImGuiDir_None) || (data->IsCenterAvailable);
    if (!is_explicit_target && !data->IsSplitDirExplicit && !g.IO.ConfigDockingWithShift)
        data->IsDropAllowed = false;

    // Calculate split area
    data->SplitRatio = 0.0f;
    if (data->SplitDir != ImGuiDir_None)
    {
        ImGuiDir split_dir = data->SplitDir;
        ImGuiAxis split_axis = (split_dir == ImGuiDir_Left || split_dir == ImGuiDir_Right) ? ImGuiAxis_X : ImGuiAxis_Y;
        ImVec2 pos_new, pos_old = data->FutureNode.Pos;
        ImVec2 size_new, size_old = data->FutureNode.Size;
        DockNodeCalcSplitRects(pos_old, size_old, pos_new, size_new, split_dir, payload_window->Size);

        // Calculate split ratio so we can pass it down the docking request
        float split_ratio = ImSaturate(size_new[split_axis] / data->FutureNode.Size[split_axis]);
        data->FutureNode.Pos = pos_new;
        data->FutureNode.Size = size_new;
        data->SplitRatio = (split_dir == ImGuiDir_Right || split_dir == ImGuiDir_Down) ? (1.0f - split_ratio) : (split_ratio);
    }
}

static void ImGui::DockNodePreviewDockRender(ImGuiWindow* host_window, ImGuiDockNode* host_node, ImGuiWindow* root_payload, const ImGuiDockPreviewData* data)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(g.CurrentWindow == host_window);   // Because we rely on font size to calculate tab sizes

    // With this option, we only display the preview on the target viewport, and the payload viewport is made transparent.
    // To compensate for the single layer obstructed by the payload, we'll increase the alpha of the preview nodes.
    const bool is_transparent_payload = g.IO.ConfigDockingTransparentPayload;

    // In case the two windows involved are on different viewports, we will draw the overlay on each of them.
    int overlay_draw_lists_count = 0;
    ImDrawList* overlay_draw_lists[2];
    overlay_draw_lists[overlay_draw_lists_count++] = GetForegroundDrawList(host_window->Viewport);
    if (host_window->Viewport != root_payload->Viewport && !is_transparent_payload)
        overlay_draw_lists[overlay_draw_lists_count++] = GetForegroundDrawList(root_payload->Viewport);

    // Draw main preview rectangle
    const ImU32 overlay_col_main = GetColorU32(ImGuiCol_DockingPreview, is_transparent_payload ? 0.60f : 0.40f);
    const ImU32 overlay_col_drop = GetColorU32(ImGuiCol_DockingPreview, is_transparent_payload ? 0.90f : 0.70f);
    const ImU32 overlay_col_drop_hovered = GetColorU32(ImGuiCol_DockingPreview, is_transparent_payload ? 1.20f : 1.00f);
    const ImU32 overlay_col_lines = GetColorU32(ImGuiCol_NavWindowingHighlight, is_transparent_payload ? 0.80f : 0.60f);

    // Display area preview
    const bool can_preview_tabs = (root_payload->DockNodeAsHost == NULL || root_payload->DockNodeAsHost->Windows.Size > 0);
    if (data->IsDropAllowed)
    {
        ImRect overlay_rect = data->FutureNode.Rect();
        if (data->SplitDir == ImGuiDir_None && can_preview_tabs)
            overlay_rect.Min.y += GetFrameHeight();
        if (data->SplitDir != ImGuiDir_None || data->IsCenterAvailable)
            for (int overlay_n = 0; overlay_n < overlay_draw_lists_count; overlay_n++)
                overlay_draw_lists[overlay_n]->AddRectFilled(overlay_rect.Min, overlay_rect.Max, overlay_col_main, host_window->WindowRounding, CalcRoundingFlagsForRectInRect(overlay_rect, host_window->Rect(), g.Style.DockingSeparatorSize));
    }

    // Display tab shape/label preview unless we are splitting node (it generally makes the situation harder to read)
    if (data->IsDropAllowed && can_preview_tabs && data->SplitDir == ImGuiDir_None && data->IsCenterAvailable)
    {
        // Compute target tab bar geometry so we can locate our preview tabs
        ImRect tab_bar_rect;
        DockNodeCalcTabBarLayout(&data->FutureNode, NULL, &tab_bar_rect, NULL, NULL);
        ImVec2 tab_pos = tab_bar_rect.Min;
        if (host_node && host_node->TabBar)
        {
            if (!host_node->IsHiddenTabBar() && !host_node->IsNoTabBar())
                tab_pos.x += host_node->TabBar->WidthAllTabs + g.Style.ItemInnerSpacing.x; // We don't use OffsetNewTab because when using non-persistent-order tab bar it is incremented with each Tab submission.
            else
                tab_pos.x += g.Style.ItemInnerSpacing.x + TabItemCalcSize(host_node->Windows[0]).x;
        }
        else if (!(host_window->Flags & ImGuiWindowFlags_DockNodeHost))
        {
            tab_pos.x += g.Style.ItemInnerSpacing.x + TabItemCalcSize(host_window).x; // Account for slight offset which will be added when changing from title bar to tab bar
        }

        // Draw tab shape/label preview (payload may be a loose window or a host window carrying multiple tabbed windows)
        if (root_payload->DockNodeAsHost)
            IM_ASSERT(root_payload->DockNodeAsHost->Windows.Size <= root_payload->DockNodeAsHost->TabBar->Tabs.Size);
        ImGuiTabBar* tab_bar_with_payload = root_payload->DockNodeAsHost ? root_payload->DockNodeAsHost->TabBar : NULL;
        const int payload_count = tab_bar_with_payload ? tab_bar_with_payload->Tabs.Size : 1;
        for (int payload_n = 0; payload_n < payload_count; payload_n++)
        {
            // DockNode's TabBar may have non-window Tabs manually appended by user
            ImGuiWindow* payload_window = tab_bar_with_payload ? tab_bar_with_payload->Tabs[payload_n].Window : root_payload;
            if (tab_bar_with_payload && payload_window == NULL)
                continue;
            if (!DockNodeIsDropAllowedOne(payload_window, host_window))
                continue;

            // Calculate the tab bounding box for each payload window
            ImVec2 tab_size = TabItemCalcSize(payload_window);
            ImRect tab_bb(tab_pos.x, tab_pos.y, tab_pos.x + tab_size.x, tab_pos.y + tab_size.y);
            tab_pos.x += tab_size.x + g.Style.ItemInnerSpacing.x;
            const ImU32 overlay_col_text = GetColorU32(payload_window->DockStyle.Colors[ImGuiWindowDockStyleCol_Text]);
            const ImU32 overlay_col_tabs = GetColorU32(payload_window->DockStyle.Colors[ImGuiWindowDockStyleCol_TabActive]);
            PushStyleColor(ImGuiCol_Text, overlay_col_text);
            for (int overlay_n = 0; overlay_n < overlay_draw_lists_count; overlay_n++)
            {
                ImGuiTabItemFlags tab_flags = (payload_window->Flags & ImGuiWindowFlags_UnsavedDocument) ? ImGuiTabItemFlags_UnsavedDocument : 0;
                if (!tab_bar_rect.Contains(tab_bb))
                    overlay_draw_lists[overlay_n]->PushClipRect(tab_bar_rect.Min, tab_bar_rect.Max);
                TabItemBackground(overlay_draw_lists[overlay_n], tab_bb, tab_flags, overlay_col_tabs);
                TabItemLabelAndCloseButton(overlay_draw_lists[overlay_n], tab_bb, tab_flags, g.Style.FramePadding, payload_window->Name, 0, 0, false, NULL, NULL);
                if (!tab_bar_rect.Contains(tab_bb))
                    overlay_draw_lists[overlay_n]->PopClipRect();
            }
            PopStyleColor();
        }
    }

    // Display drop boxes
    const float overlay_rounding = ImMax(3.0f, g.Style.FrameRounding);
    for (int dir = ImGuiDir_None; dir < ImGuiDir_COUNT; dir++)
    {
        if (!data->DropRectsDraw[dir + 1].IsInverted())
        {
            ImRect draw_r = data->DropRectsDraw[dir + 1];
            ImRect draw_r_in = draw_r;
            draw_r_in.Expand(-2.0f);
            ImU32 overlay_col = (data->SplitDir == (ImGuiDir)dir && data->IsSplitDirExplicit) ? overlay_col_drop_hovered : overlay_col_drop;
            for (int overlay_n = 0; overlay_n < overlay_draw_lists_count; overlay_n++)
            {
                ImVec2 center = ImFloor(draw_r_in.GetCenter());
                overlay_draw_lists[overlay_n]->AddRectFilled(draw_r.Min, draw_r.Max, overlay_col, overlay_rounding);
                overlay_draw_lists[overlay_n]->AddRect(draw_r_in.Min, draw_r_in.Max, overlay_col_lines, overlay_rounding);
                if (dir == ImGuiDir_Left || dir == ImGuiDir_Right)
                    overlay_draw_lists[overlay_n]->AddLine(ImVec2(center.x, draw_r_in.Min.y), ImVec2(center.x, draw_r_in.Max.y), overlay_col_lines);
                if (dir == ImGuiDir_Up || dir == ImGuiDir_Down)
                    overlay_draw_lists[overlay_n]->AddLine(ImVec2(draw_r_in.Min.x, center.y), ImVec2(draw_r_in.Max.x, center.y), overlay_col_lines);
            }
        }

        // Stop after ImGuiDir_None
        if ((host_node && (host_node->MergedFlags & ImGuiDockNodeFlags_NoDockingSplit)) || g.IO.ConfigDockingNoSplit)
            return;
    }
}

//-----------------------------------------------------------------------------
// Docking: ImGuiDockNode Tree manipulation functions
//-----------------------------------------------------------------------------
// - DockNodeTreeSplit()
// - DockNodeTreeMerge()
// - DockNodeTreeUpdatePosSize()
// - DockNodeTreeUpdateSplitterFindTouchingNode()
// - DockNodeTreeUpdateSplitter()
// - DockNodeTreeFindFallbackLeafNode()
// - DockNodeTreeFindNodeByPos()
//-----------------------------------------------------------------------------

void ImGui::DockNodeTreeSplit(ImGuiContext* ctx, ImGuiDockNode* parent_node, ImGuiAxis split_axis, int split_inheritor_child_idx, float split_ratio, ImGuiDockNode* new_node)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(split_axis != ImGuiAxis_None);

    ImGuiDockNode* child_0 = (new_node && split_inheritor_child_idx != 0) ? new_node : DockContextAddNode(ctx, 0);
    child_0->ParentNode = parent_node;

    ImGuiDockNode* child_1 = (new_node && split_inheritor_child_idx != 1) ? new_node : DockContextAddNode(ctx, 0);
    child_1->ParentNode = parent_node;

    ImGuiDockNode* child_inheritor = (split_inheritor_child_idx == 0) ? child_0 : child_1;
    DockNodeMoveChildNodes(child_inheritor, parent_node);
    parent_node->ChildNodes[0] = child_0;
    parent_node->ChildNodes[1] = child_1;
    parent_node->ChildNodes[split_inheritor_child_idx]->VisibleWindow = parent_node->VisibleWindow;
    parent_node->SplitAxis = split_axis;
    parent_node->VisibleWindow = NULL;
    parent_node->AuthorityForPos = parent_node->AuthorityForSize = ImGuiDataAuthority_DockNode;

    float size_avail = (parent_node->Size[split_axis] - g.Style.DockingSeparatorSize);
    size_avail = ImMax(size_avail, g.Style.WindowMinSize[split_axis] * 2.0f);
    IM_ASSERT(size_avail > 0.0f); // If you created a node manually with DockBuilderAddNode(), you need to also call DockBuilderSetNodeSize() before splitting.
    child_0->SizeRef = child_1->SizeRef = parent_node->Size;
    child_0->SizeRef[split_axis] = ImTrunc(size_avail * split_ratio);
    child_1->SizeRef[split_axis] = ImTrunc(size_avail - child_0->SizeRef[split_axis]);

    DockNodeMoveWindows(parent_node->ChildNodes[split_inheritor_child_idx], parent_node);
    DockSettingsRenameNodeReferences(parent_node->ID, parent_node->ChildNodes[split_inheritor_child_idx]->ID);
    DockNodeUpdateHasCentralNodeChild(DockNodeGetRootNode(parent_node));
    DockNodeTreeUpdatePosSize(parent_node, parent_node->Pos, parent_node->Size);

    // Flags transfer (e.g. this is where we transfer the ImGuiDockNodeFlags_CentralNode property)
    child_0->SharedFlags = parent_node->SharedFlags & ImGuiDockNodeFlags_SharedFlagsInheritMask_;
    child_1->SharedFlags = parent_node->SharedFlags & ImGuiDockNodeFlags_SharedFlagsInheritMask_;
    child_inheritor->LocalFlags = parent_node->LocalFlags & ImGuiDockNodeFlags_LocalFlagsTransferMask_;
    parent_node->LocalFlags &= ~ImGuiDockNodeFlags_LocalFlagsTransferMask_;
    child_0->UpdateMergedFlags();
    child_1->UpdateMergedFlags();
    parent_node->UpdateMergedFlags();
    if (child_inheritor->IsCentralNode())
        DockNodeGetRootNode(parent_node)->CentralNode = child_inheritor;
}

void ImGui::DockNodeTreeMerge(ImGuiContext* ctx, ImGuiDockNode* parent_node, ImGuiDockNode* merge_lead_child)
{
    // When called from DockContextProcessUndockNode() it is possible that one of the child is NULL.
    ImGuiContext& g = *GImGui;
    ImGuiDockNode* child_0 = parent_node->ChildNodes[0];
    ImGuiDockNode* child_1 = parent_node->ChildNodes[1];
    IM_ASSERT(child_0 || child_1);
    IM_ASSERT(merge_lead_child == child_0 || merge_lead_child == child_1);
    if ((child_0 && child_0->Windows.Size > 0) || (child_1 && child_1->Windows.Size > 0))
    {
        IM_ASSERT(parent_node->TabBar == NULL);
        IM_ASSERT(parent_node->Windows.Size == 0);
    }
    IMGUI_DEBUG_LOG_DOCKING("[docking] DockNodeTreeMerge: 0x%08X + 0x%08X back into parent 0x%08X\n", child_0 ? child_0->ID : 0, child_1 ? child_1->ID : 0, parent_node->ID);

    ImVec2 backup_last_explicit_size = parent_node->SizeRef;
    DockNodeMoveChildNodes(parent_node, merge_lead_child);
    if (child_0)
    {
        DockNodeMoveWindows(parent_node, child_0); // Generally only 1 of the 2 child node will have windows
        DockSettingsRenameNodeReferences(child_0->ID, parent_node->ID);
    }
    if (child_1)
    {
        DockNodeMoveWindows(parent_node, child_1);
        DockSettingsRenameNodeReferences(child_1->ID, parent_node->ID);
    }
    DockNodeApplyPosSizeToWindows(parent_node);
    parent_node->AuthorityForPos = parent_node->AuthorityForSize = parent_node->AuthorityForViewport = ImGuiDataAuthority_Auto;
    parent_node->VisibleWindow = merge_lead_child->VisibleWindow;
    parent_node->SizeRef = backup_last_explicit_size;

    // Flags transfer
    parent_node->LocalFlags &= ~ImGuiDockNodeFlags_LocalFlagsTransferMask_; // Preserve Dockspace flag
    parent_node->LocalFlags |= (child_0 ? child_0->LocalFlags : 0) & ImGuiDockNodeFlags_LocalFlagsTransferMask_;
    parent_node->LocalFlags |= (child_1 ? child_1->LocalFlags : 0) & ImGuiDockNodeFlags_LocalFlagsTransferMask_;
    parent_node->LocalFlagsInWindows = (child_0 ? child_0->LocalFlagsInWindows : 0) | (child_1 ? child_1->LocalFlagsInWindows : 0); // FIXME: Would be more consistent to update from actual windows
    parent_node->UpdateMergedFlags();

    if (child_0)
    {
        ctx->DockContext.Nodes.SetVoidPtr(child_0->ID, NULL);
        IM_DELETE(child_0);
    }
    if (child_1)
    {
        ctx->DockContext.Nodes.SetVoidPtr(child_1->ID, NULL);
        IM_DELETE(child_1);
    }
}

// Update Pos/Size for a node hierarchy (don't affect child Windows yet)
// (Depth-first, Pre-Order)
void ImGui::DockNodeTreeUpdatePosSize(ImGuiDockNode* node, ImVec2 pos, ImVec2 size, ImGuiDockNode* only_write_to_single_node)
{
    // During the regular dock node update we write to all nodes.
    // 'only_write_to_single_node' is only set when turning a node visible mid-frame and we need its size right-away.
    ImGuiContext& g = *GImGui;
    const bool write_to_node = only_write_to_single_node == NULL || only_write_to_single_node == node;
    if (write_to_node)
    {
        node->Pos = pos;
        node->Size = size;
    }

    if (node->IsLeafNode())
        return;

    ImGuiDockNode* child_0 = node->ChildNodes[0];
    ImGuiDockNode* child_1 = node->ChildNodes[1];
    ImVec2 child_0_pos = pos, child_1_pos = pos;
    ImVec2 child_0_size = size, child_1_size = size;

    const bool child_0_is_toward_single_node = (only_write_to_single_node != NULL && DockNodeIsInHierarchyOf(only_write_to_single_node, child_0));
    const bool child_1_is_toward_single_node = (only_write_to_single_node != NULL && DockNodeIsInHierarchyOf(only_write_to_single_node, child_1));
    const bool child_0_is_or_will_be_visible = child_0->IsVisible || child_0_is_toward_single_node;
    const bool child_1_is_or_will_be_visible = child_1->IsVisible || child_1_is_toward_single_node;

    if (child_0_is_or_will_be_visible && child_1_is_or_will_be_visible)
    {
        const float spacing = g.Style.DockingSeparatorSize;
        const ImGuiAxis axis = (ImGuiAxis)node->SplitAxis;
        const float size_avail = ImMax(size[axis] - spacing, 0.0f);

        // Size allocation policy
        // 1) The first 0..WindowMinSize[axis]*2 are allocated evenly to both windows.
        const float size_min_each = ImTrunc(ImMin(size_avail, g.Style.WindowMinSize[axis] * 2.0f) * 0.5f);

        // FIXME: Blocks 2) and 3) are essentially doing nearly the same thing.
        // Difference are: write-back to SizeRef; application of a minimum size; rounding before ImTrunc()
        // Clarify and rework differences between Size & SizeRef and purpose of WantLockSizeOnce

        // 2) Process locked absolute size (during a splitter resize we preserve the child of nodes not touching the splitter edge)
        if (child_0->WantLockSizeOnce && !child_1->WantLockSizeOnce)
        {
            child_0_size[axis] = child_0->SizeRef[axis] = ImMin(size_avail - 1.0f, child_0->Size[axis]);
            child_1_size[axis] = child_1->SizeRef[axis] = (size_avail - child_0_size[axis]);
            IM_ASSERT(child_0->SizeRef[axis] > 0.0f && child_1->SizeRef[axis] > 0.0f);
        }
        else if (child_1->WantLockSizeOnce && !child_0->WantLockSizeOnce)
        {
            child_1_size[axis] = child_1->SizeRef[axis] = ImMin(size_avail - 1.0f, child_1->Size[axis]);
            child_0_size[axis] = child_0->SizeRef[axis] = (size_avail - child_1_size[axis]);
            IM_ASSERT(child_0->SizeRef[axis] > 0.0f && child_1->SizeRef[axis] > 0.0f);
        }
        else if (child_0->WantLockSizeOnce && child_1->WantLockSizeOnce)
        {
            // FIXME-DOCK: We cannot honor the requested size, so apply ratio.
            // Currently this path will only be taken if code programmatically sets WantLockSizeOnce
            float split_ratio = child_0_size[axis] / (child_0_size[axis] + child_1_size[axis]);
            child_0_size[axis] = child_0->SizeRef[axis] = ImTrunc(size_avail * split_ratio);
            child_1_size[axis] = child_1->SizeRef[axis] = (size_avail - child_0_size[axis]);
            IM_ASSERT(child_0->SizeRef[axis] > 0.0f && child_1->SizeRef[axis] > 0.0f);
        }

        // 3) If one window is the central node (~ use remaining space, should be made explicit!), use explicit size from the other, and remainder for the central node
        else if (child_0->SizeRef[axis] != 0.0f && child_1->HasCentralNodeChild)
        {
            child_0_size[axis] = ImMin(size_avail - size_min_each, child_0->SizeRef[axis]);
            child_1_size[axis] = (size_avail - child_0_size[axis]);
        }
        else if (child_1->SizeRef[axis] != 0.0f && child_0->HasCentralNodeChild)
        {
            child_1_size[axis] = ImMin(size_avail - size_min_each, child_1->SizeRef[axis]);
            child_0_size[axis] = (size_avail - child_1_size[axis]);
        }
        else
        {
            // 4) Otherwise distribute according to the relative ratio of each SizeRef value
            float split_ratio = child_0->SizeRef[axis] / (child_0->SizeRef[axis] + child_1->SizeRef[axis]);
            child_0_size[axis] = ImMax(size_min_each, ImTrunc(size_avail * split_ratio + 0.5f));
            child_1_size[axis] = (size_avail - child_0_size[axis]);
        }

        child_1_pos[axis] += spacing + child_0_size[axis];
    }

    if (only_write_to_single_node == NULL)
        child_0->WantLockSizeOnce = child_1->WantLockSizeOnce = false;

    const bool child_0_recurse = only_write_to_single_node ? child_0_is_toward_single_node : child_0->IsVisible;
    const bool child_1_recurse = only_write_to_single_node ? child_1_is_toward_single_node : child_1->IsVisible;
    if (child_0_recurse)
        DockNodeTreeUpdatePosSize(child_0, child_0_pos, child_0_size);
    if (child_1_recurse)
        DockNodeTreeUpdatePosSize(child_1, child_1_pos, child_1_size);
}

static void DockNodeTreeUpdateSplitterFindTouchingNode(ImGuiDockNode* node, ImGuiAxis axis, int side, ImVector<ImGuiDockNode*>* touching_nodes)
{
    if (node->IsLeafNode())
    {
        touching_nodes->push_back(node);
        return;
    }
    if (node->ChildNodes[0]->IsVisible)
        if (node->SplitAxis != axis || side == 0 || !node->ChildNodes[1]->IsVisible)
            DockNodeTreeUpdateSplitterFindTouchingNode(node->ChildNodes[0], axis, side, touching_nodes);
    if (node->ChildNodes[1]->IsVisible)
        if (node->SplitAxis != axis || side == 1 || !node->ChildNodes[0]->IsVisible)
            DockNodeTreeUpdateSplitterFindTouchingNode(node->ChildNodes[1], axis, side, touching_nodes);
}

// (Depth-First, Pre-Order)
void ImGui::DockNodeTreeUpdateSplitter(ImGuiDockNode* node)
{
    if (node->IsLeafNode())
        return;

    ImGuiContext& g = *GImGui;

    ImGuiDockNode* child_0 = node->ChildNodes[0];
    ImGuiDockNode* child_1 = node->ChildNodes[1];
    if (child_0->IsVisible && child_1->IsVisible)
    {
        // Bounding box of the splitter cover the space between both nodes (w = Spacing, h = Size[xy^1] for when splitting horizontally)
        const ImGuiAxis axis = (ImGuiAxis)node->SplitAxis;
        IM_ASSERT(axis != ImGuiAxis_None);
        ImRect bb;
        bb.Min = child_0->Pos;
        bb.Max = child_1->Pos;
        bb.Min[axis] += child_0->Size[axis];
        bb.Max[axis ^ 1] += child_1->Size[axis ^ 1];
        //if (g.IO.KeyCtrl) GetForegroundDrawList(g.CurrentWindow->Viewport)->AddRect(bb.Min, bb.Max, IM_COL32(255,0,255,255));

        const ImGuiDockNodeFlags merged_flags = child_0->MergedFlags | child_1->MergedFlags; // Merged flags for BOTH childs
        const ImGuiDockNodeFlags no_resize_axis_flag = (axis == ImGuiAxis_X) ? ImGuiDockNodeFlags_NoResizeX : ImGuiDockNodeFlags_NoResizeY;
        if ((merged_flags & ImGuiDockNodeFlags_NoResize) || (merged_flags & no_resize_axis_flag))
        {
            ImGuiWindow* window = g.CurrentWindow;
            window->DrawList->AddRectFilled(bb.Min, bb.Max, GetColorU32(ImGuiCol_Separator), g.Style.FrameRounding);
        }
        else
        {
            //bb.Min[axis] += 1; // Display a little inward so highlight doesn't connect with nearby tabs on the neighbor node.
            //bb.Max[axis] -= 1;
            PushID(node->ID);

            // Find resizing limits by gathering list of nodes that are touching the splitter line.
            ImVector<ImGuiDockNode*> touching_nodes[2];
            float min_size = g.Style.WindowMinSize[axis];
            float resize_limits[2];
            resize_limits[0] = node->ChildNodes[0]->Pos[axis] + min_size;
            resize_limits[1] = node->ChildNodes[1]->Pos[axis] + node->ChildNodes[1]->Size[axis] - min_size;

            ImGuiID splitter_id = GetID("##Splitter");
            if (g.ActiveId == splitter_id) // Only process when splitter is active
            {
                DockNodeTreeUpdateSplitterFindTouchingNode(child_0, axis, 1, &touching_nodes[0]);
                DockNodeTreeUpdateSplitterFindTouchingNode(child_1, axis, 0, &touching_nodes[1]);
                for (int touching_node_n = 0; touching_node_n < touching_nodes[0].Size; touching_node_n++)
                    resize_limits[0] = ImMax(resize_limits[0], touching_nodes[0][touching_node_n]->Rect().Min[axis] + min_size);
                for (int touching_node_n = 0; touching_node_n < touching_nodes[1].Size; touching_node_n++)
                    resize_limits[1] = ImMin(resize_limits[1], touching_nodes[1][touching_node_n]->Rect().Max[axis] - min_size);

                // [DEBUG] Render touching nodes & limits
                /*
                ImDrawList* draw_list = node->HostWindow ? GetForegroundDrawList(node->HostWindow) : GetForegroundDrawList(GetMainViewport());
                for (int n = 0; n < 2; n++)
                {
                    for (int touching_node_n = 0; touching_node_n < touching_nodes[n].Size; touching_node_n++)
                        draw_list->AddRect(touching_nodes[n][touching_node_n]->Pos, touching_nodes[n][touching_node_n]->Pos + touching_nodes[n][touching_node_n]->Size, IM_COL32(0, 255, 0, 255));
                    if (axis == ImGuiAxis_X)
                        draw_list->AddLine(ImVec2(resize_limits[n], node->ChildNodes[n]->Pos.y), ImVec2(resize_limits[n], node->ChildNodes[n]->Pos.y + node->ChildNodes[n]->Size.y), IM_COL32(255, 0, 255, 255), 3.0f);
                    else
                        draw_list->AddLine(ImVec2(node->ChildNodes[n]->Pos.x, resize_limits[n]), ImVec2(node->ChildNodes[n]->Pos.x + node->ChildNodes[n]->Size.x, resize_limits[n]), IM_COL32(255, 0, 255, 255), 3.0f);
                }
                */
            }

            // Use a short delay before highlighting the splitter (and changing the mouse cursor) in order for regular mouse movement to not highlight many splitters
            float cur_size_0 = child_0->Size[axis];
            float cur_size_1 = child_1->Size[axis];
            float min_size_0 = resize_limits[0] - child_0->Pos[axis];
            float min_size_1 = child_1->Pos[axis] + child_1->Size[axis] - resize_limits[1];
            ImU32 bg_col = GetColorU32(ImGuiCol_WindowBg);
            if (SplitterBehavior(bb, GetID("##Splitter"), axis, &cur_size_0, &cur_size_1, min_size_0, min_size_1, WINDOWS_HOVER_PADDING, WINDOWS_RESIZE_FROM_EDGES_FEEDBACK_TIMER, bg_col))
            {
                if (touching_nodes[0].Size > 0 && touching_nodes[1].Size > 0)
                {
                    child_0->Size[axis] = child_0->SizeRef[axis] = cur_size_0;
                    child_1->Pos[axis] -= cur_size_1 - child_1->Size[axis];
                    child_1->Size[axis] = child_1->SizeRef[axis] = cur_size_1;

                    // Lock the size of every node that is a sibling of the node we are touching
                    // This might be less desirable if we can merge sibling of a same axis into the same parental level.
                    for (int side_n = 0; side_n < 2; side_n++)
                        for (int touching_node_n = 0; touching_node_n < touching_nodes[side_n].Size; touching_node_n++)
                        {
                            ImGuiDockNode* touching_node = touching_nodes[side_n][touching_node_n];
                            //ImDrawList* draw_list = node->HostWindow ? GetForegroundDrawList(node->HostWindow) : GetForegroundDrawList(GetMainViewport());
                            //draw_list->AddRect(touching_node->Pos, touching_node->Pos + touching_node->Size, IM_COL32(255, 128, 0, 255));
                            while (touching_node->ParentNode != node)
                            {
                                if (touching_node->ParentNode->SplitAxis == axis)
                                {
                                    // Mark other node so its size will be preserved during the upcoming call to DockNodeTreeUpdatePosSize().
                                    ImGuiDockNode* node_to_preserve = touching_node->ParentNode->ChildNodes[side_n];
                                    node_to_preserve->WantLockSizeOnce = true;
                                    //draw_list->AddRect(touching_node->Pos, touching_node->Rect().Max, IM_COL32(255, 0, 0, 255));
                                    //draw_list->AddRectFilled(node_to_preserve->Pos, node_to_preserve->Rect().Max, IM_COL32(0, 255, 0, 100));
                                }
                                touching_node = touching_node->ParentNode;
                            }
                        }

                    DockNodeTreeUpdatePosSize(child_0, child_0->Pos, child_0->Size);
                    DockNodeTreeUpdatePosSize(child_1, child_1->Pos, child_1->Size);
                    MarkIniSettingsDirty();
                }
            }
            PopID();
        }
    }

    if (child_0->IsVisible)
        DockNodeTreeUpdateSplitter(child_0);
    if (child_1->IsVisible)
        DockNodeTreeUpdateSplitter(child_1);
}

ImGuiDockNode* ImGui::DockNodeTreeFindFallbackLeafNode(ImGuiDockNode* node)
{
    if (node->IsLeafNode())
        return node;
    if (ImGuiDockNode* leaf_node = DockNodeTreeFindFallbackLeafNode(node->ChildNodes[0]))
        return leaf_node;
    if (ImGuiDockNode* leaf_node = DockNodeTreeFindFallbackLeafNode(node->ChildNodes[1]))
        return leaf_node;
    return NULL;
}

ImGuiDockNode* ImGui::DockNodeTreeFindVisibleNodeByPos(ImGuiDockNode* node, ImVec2 pos)
{
    if (!node->IsVisible)
        return NULL;

    const float dock_spacing = 0.0f;// g.Style.ItemInnerSpacing.x; // FIXME: Relation to DOCKING_SPLITTER_SIZE?
    ImRect r(node->Pos, node->Pos + node->Size);
    r.Expand(dock_spacing * 0.5f);
    bool inside = r.Contains(pos);
    if (!inside)
        return NULL;

    if (node->IsLeafNode())
        return node;
    if (ImGuiDockNode* hovered_node = DockNodeTreeFindVisibleNodeByPos(node->ChildNodes[0], pos))
        return hovered_node;
    if (ImGuiDockNode* hovered_node = DockNodeTreeFindVisibleNodeByPos(node->ChildNodes[1], pos))
        return hovered_node;

    // This means we are hovering over the splitter/spacing of a parent node
    return node;
}

//-----------------------------------------------------------------------------
// Docking: Public Functions (SetWindowDock, DockSpace, DockSpaceOverViewport)
//-----------------------------------------------------------------------------
// - SetWindowDock() [Internal]
// - DockSpace()
// - DockSpaceOverViewport()
//-----------------------------------------------------------------------------

// [Internal] Called via SetNextWindowDockID()
void ImGui::SetWindowDock(ImGuiWindow* window, ImGuiID dock_id, ImGuiCond cond)
{
    // Test condition (NB: bit 0 is always true) and clear flags for next time
    if (cond && (window->SetWindowDockAllowFlags & cond) == 0)
        return;
    window->SetWindowDockAllowFlags &= ~(ImGuiCond_Once | ImGuiCond_FirstUseEver | ImGuiCond_Appearing);

    if (window->DockId == dock_id)
        return;

    // If the user attempt to set a dock id that is a split node, we'll dig within to find a suitable docking spot
    ImGuiContext* ctx = GImGui;
    if (ImGuiDockNode* new_node = DockContextFindNodeByID(ctx, dock_id))
        if (new_node->IsSplitNode())
        {
            // Policy: Find central node or latest focused node. We first move back to our root node.
            new_node = DockNodeGetRootNode(new_node);
            if (new_node->CentralNode)
            {
                IM_ASSERT(new_node->CentralNode->IsCentralNode());
                dock_id = new_node->CentralNode->ID;
            }
            else
            {
                dock_id = new_node->LastFocusedNodeId;
            }
        }

    if (window->DockId == dock_id)
        return;

    if (window->DockNode)
        DockNodeRemoveWindow(window->DockNode, window, 0);
    window->DockId = dock_id;
}

// Create an explicit dockspace node within an existing window. Also expose dock node flags and creates a CentralNode by default.
// The Central Node is always displayed even when empty and shrink/extend according to the requested size of its neighbors.
// DockSpace() needs to be submitted _before_ any window they can host. If you use a dockspace, submit it early in your app.
// When ImGuiDockNodeFlags_KeepAliveOnly is set, nothing is submitted in the current window (function may be called from any location).
ImGuiID ImGui::DockSpace(ImGuiID id, const ImVec2& size_arg, ImGuiDockNodeFlags flags, const ImGuiWindowClass* window_class)
{
    ImGuiContext* ctx = GImGui;
    ImGuiContext& g = *ctx;
    ImGuiWindow* window = GetCurrentWindowRead();
    if (!(g.IO.ConfigFlags & ImGuiConfigFlags_DockingEnable))
        return 0;

    // Early out if parent window is hidden/collapsed
    // This is faster but also DockNodeUpdateTabBar() relies on TabBarLayout() running (which won't if SkipItems=true) to set NextSelectedTabId = 0). See #2960.
    // If for whichever reason this is causing problem we would need to ensure that DockNodeUpdateTabBar() ends up clearing NextSelectedTabId even if SkipItems=true.
    if (window->SkipItems)
        flags |= ImGuiDockNodeFlags_KeepAliveOnly;
    if ((flags & ImGuiDockNodeFlags_KeepAliveOnly) == 0)
        window = GetCurrentWindow(); // call to set window->WriteAccessed = true;

    IM_ASSERT((flags & ImGuiDockNodeFlags_DockSpace) == 0);
    IM_ASSERT(id != 0);
    ImGuiDockNode* node = DockContextFindNodeByID(ctx, id);
    if (!node)
    {
        IMGUI_DEBUG_LOG_DOCKING("[docking] DockSpace: dockspace node 0x%08X created\n", id);
        node = DockContextAddNode(ctx, id);
        node->SetLocalFlags(ImGuiDockNodeFlags_CentralNode);
    }
    if (window_class && window_class->ClassId != node->WindowClass.ClassId)
        IMGUI_DEBUG_LOG_DOCKING("[docking] DockSpace: dockspace node 0x%08X: setup WindowClass 0x%08X -> 0x%08X\n", id, node->WindowClass.ClassId, window_class->ClassId);
    node->SharedFlags = flags;
    node->WindowClass = window_class ? *window_class : ImGuiWindowClass();

    // When a DockSpace transitioned form implicit to explicit this may be called a second time
    // It is possible that the node has already been claimed by a docked window which appeared before the DockSpace() node, so we overwrite IsDockSpace again.
    if (node->LastFrameActive == g.FrameCount && !(flags & ImGuiDockNodeFlags_KeepAliveOnly))
    {
        IM_ASSERT(node->IsDockSpace() == false && "Cannot call DockSpace() twice a frame with the same ID");
        node->SetLocalFlags(node->LocalFlags | ImGuiDockNodeFlags_DockSpace);
        return id;
    }
    node->SetLocalFlags(node->LocalFlags | ImGuiDockNodeFlags_DockSpace);

    // Keep alive mode, this is allow windows docked into this node so stay docked even if they are not visible
    if (flags & ImGuiDockNodeFlags_KeepAliveOnly)
    {
        node->LastFrameAlive = g.FrameCount;
        return id;
    }

    const ImVec2 content_avail = GetContentRegionAvail();
    ImVec2 size = ImTrunc(size_arg);
    if (size.x <= 0.0f)
        size.x = ImMax(content_avail.x + size.x, 4.0f); // Arbitrary minimum child size (0.0f causing too much issues)
    if (size.y <= 0.0f)
        size.y = ImMax(content_avail.y + size.y, 4.0f);
    IM_ASSERT(size.x > 0.0f && size.y > 0.0f);

    node->Pos = window->DC.CursorPos;
    node->Size = node->SizeRef = size;
    SetNextWindowPos(node->Pos);
    SetNextWindowSize(node->Size);
    g.NextWindowData.PosUndock = false;

    // FIXME-DOCK: Why do we need a child window to host a dockspace, could we host it in the existing window?
    // FIXME-DOCK: What is the reason for not simply calling BeginChild()? (OK to have a reason but should be commented)
    ImGuiWindowFlags window_flags = ImGuiWindowFlags_ChildWindow | ImGuiWindowFlags_DockNodeHost;
    window_flags |= ImGuiWindowFlags_NoSavedSettings | ImGuiWindowFlags_NoResize | ImGuiWindowFlags_NoCollapse | ImGuiWindowFlags_NoTitleBar;
    window_flags |= ImGuiWindowFlags_NoScrollbar | ImGuiWindowFlags_NoScrollWithMouse;
    window_flags |= ImGuiWindowFlags_NoBackground;

    char title[256];
    ImFormatString(title, IM_ARRAYSIZE(title), "%s/DockSpace_%08X", window->Name, id);

    PushStyleVar(ImGuiStyleVar_ChildBorderSize, 0.0f);
    Begin(title, NULL, window_flags);
    PopStyleVar();

    ImGuiWindow* host_window = g.CurrentWindow;
    DockNodeSetupHostWindow(node, host_window);
    host_window->ChildId = window->GetID(title);
    node->OnlyNodeWithWindows = NULL;

    IM_ASSERT(node->IsRootNode());

    // We need to handle the rare case were a central node is missing.
    // This can happen if the node was first created manually with DockBuilderAddNode() but _without_ the ImGuiDockNodeFlags_Dockspace.
    // Doing it correctly would set the _CentralNode flags, which would then propagate according to subsequent split.
    // It would also be ambiguous to attempt to assign a central node while there are split nodes, so we wait until there's a single node remaining.
    // The specific sub-property of _CentralNode we are interested in recovering here is the "Don't delete when empty" property,
    // as it doesn't make sense for an empty dockspace to not have this property.
    if (node->IsLeafNode() && !node->IsCentralNode())
        node->SetLocalFlags(node->LocalFlags | ImGuiDockNodeFlags_CentralNode);

    // Update the node
    DockNodeUpdate(node);

    End();

    ImRect bb(node->Pos, node->Pos + size);
    ItemSize(size);
    ItemAdd(bb, id, NULL, ImGuiItemFlags_NoNav); // Not a nav point (could be, would need to draw the nav rect and replicate/refactor activation from BeginChild(), but seems like CTRL+Tab works better here?)
    if ((g.LastItemData.StatusFlags & ImGuiItemStatusFlags_HoveredRect) && IsWindowChildOf(g.HoveredWindow, host_window, false, true)) // To fullfill IsItemHovered(), similar to EndChild()
        g.LastItemData.StatusFlags |= ImGuiItemStatusFlags_HoveredWindow;

    return id;
}

// Tips: Use with ImGuiDockNodeFlags_PassthruCentralNode!
// The limitation with this call is that your window won't have a menu bar.
// Even though we could pass window flags, it would also require the user to be able to call BeginMenuBar() somehow meaning we can't Begin/End in a single function.
// But you can also use BeginMainMenuBar(). If you really want a menu bar inside the same window as the one hosting the dockspace, you will need to copy this code somewhere and tweak it.
ImGuiID ImGui::DockSpaceOverViewport(const ImGuiViewport* viewport, ImGuiDockNodeFlags dockspace_flags, const ImGuiWindowClass* window_class)
{
    if (viewport == NULL)
        viewport = GetMainViewport();

    SetNextWindowPos(viewport->WorkPos);
    SetNextWindowSize(viewport->WorkSize);
    SetNextWindowViewport(viewport->ID);

    ImGuiWindowFlags host_window_flags = 0;
    host_window_flags |= ImGuiWindowFlags_NoTitleBar | ImGuiWindowFlags_NoCollapse | ImGuiWindowFlags_NoResize | ImGuiWindowFlags_NoMove | ImGuiWindowFlags_NoDocking;
    host_window_flags |= ImGuiWindowFlags_NoBringToFrontOnFocus | ImGuiWindowFlags_NoNavFocus;
    if (dockspace_flags & ImGuiDockNodeFlags_PassthruCentralNode)
        host_window_flags |= ImGuiWindowFlags_NoBackground;

    char label[32];
    ImFormatString(label, IM_ARRAYSIZE(label), "DockSpaceViewport_%08X", viewport->ID);

    PushStyleVar(ImGuiStyleVar_WindowRounding, 0.0f);
    PushStyleVar(ImGuiStyleVar_WindowBorderSize, 0.0f);
    PushStyleVar(ImGuiStyleVar_WindowPadding, ImVec2(0.0f, 0.0f));
    Begin(label, NULL, host_window_flags);
    PopStyleVar(3);

    ImGuiID dockspace_id = GetID("DockSpace");
    DockSpace(dockspace_id, ImVec2(0.0f, 0.0f), dockspace_flags, window_class);
    End();

    return dockspace_id;
}

//-----------------------------------------------------------------------------
// Docking: Builder Functions
//-----------------------------------------------------------------------------
// Very early end-user API to manipulate dock nodes.
// Only available in imgui_internal.h. Expect this API to change/break!
// It is expected that those functions are all called _before_ the dockspace node submission.
//-----------------------------------------------------------------------------
// - DockBuilderDockWindow()
// - DockBuilderGetNode()
// - DockBuilderSetNodePos()
// - DockBuilderSetNodeSize()
// - DockBuilderAddNode()
// - DockBuilderRemoveNode()
// - DockBuilderRemoveNodeChildNodes()
// - DockBuilderRemoveNodeDockedWindows()
// - DockBuilderSplitNode()
// - DockBuilderCopyNodeRec()
// - DockBuilderCopyNode()
// - DockBuilderCopyWindowSettings()
// - DockBuilderCopyDockSpace()
// - DockBuilderFinish()
//-----------------------------------------------------------------------------

void ImGui::DockBuilderDockWindow(const char* window_name, ImGuiID node_id)
{
    // We don't preserve relative order of multiple docked windows (by clearing DockOrder back to -1)
    ImGuiContext& g = *GImGui; IM_UNUSED(g);
    IMGUI_DEBUG_LOG_DOCKING("[docking] DockBuilderDockWindow '%s' to node 0x%08X\n", window_name, node_id);
    ImGuiID window_id = ImHashStr(window_name);
    if (ImGuiWindow* window = FindWindowByID(window_id))
    {
        // Apply to created window
        ImGuiID prev_node_id = window->DockId;
        SetWindowDock(window, node_id, ImGuiCond_Always);
        if (window->DockId != prev_node_id)
            window->DockOrder = -1;
    }
    else
    {
        // Apply to settings
        ImGuiWindowSettings* settings = FindWindowSettingsByID(window_id);
        if (settings == NULL)
            settings = CreateNewWindowSettings(window_name);
        if (settings->DockId != node_id)
            settings->DockOrder = -1;
        settings->DockId = node_id;
    }
}

ImGuiDockNode* ImGui::DockBuilderGetNode(ImGuiID node_id)
{
    ImGuiContext* ctx = GImGui;
    return DockContextFindNodeByID(ctx, node_id);
}

void ImGui::DockBuilderSetNodePos(ImGuiID node_id, ImVec2 pos)
{
    ImGuiContext* ctx = GImGui;
    ImGuiDockNode* node = DockContextFindNodeByID(ctx, node_id);
    if (node == NULL)
        return;
    node->Pos = pos;
    node->AuthorityForPos = ImGuiDataAuthority_DockNode;
}

void ImGui::DockBuilderSetNodeSize(ImGuiID node_id, ImVec2 size)
{
    ImGuiContext* ctx = GImGui;
    ImGuiDockNode* node = DockContextFindNodeByID(ctx, node_id);
    if (node == NULL)
        return;
    IM_ASSERT(size.x > 0.0f && size.y > 0.0f);
    node->Size = node->SizeRef = size;
    node->AuthorityForSize = ImGuiDataAuthority_DockNode;
}

// Make sure to use the ImGuiDockNodeFlags_DockSpace flag to create a dockspace node! Otherwise this will create a floating node!
// - Floating node: you can then call DockBuilderSetNodePos()/DockBuilderSetNodeSize() to position and size the floating node.
// - Dockspace node: calling DockBuilderSetNodePos() is unnecessary.
// - If you intend to split a node immediately after creation using DockBuilderSplitNode(), make sure to call DockBuilderSetNodeSize() beforehand!
//   For various reason, the splitting code currently needs a base size otherwise space may not be allocated as precisely as you would expect.
// - Use (id == 0) to let the system allocate a node identifier.
// - Existing node with a same id will be removed.
ImGuiID ImGui::DockBuilderAddNode(ImGuiID node_id, ImGuiDockNodeFlags flags)
{
    ImGuiContext* ctx = GImGui;
    ImGuiContext& g = *ctx; IM_UNUSED(g);
    IMGUI_DEBUG_LOG_DOCKING("[docking] DockBuilderAddNode 0x%08X flags=%08X\n", node_id, flags);

    if (node_id != 0)
        DockBuilderRemoveNode(node_id);

    ImGuiDockNode* node = NULL;
    if (flags & ImGuiDockNodeFlags_DockSpace)
    {
        DockSpace(node_id, ImVec2(0, 0), (flags & ~ImGuiDockNodeFlags_DockSpace) | ImGuiDockNodeFlags_KeepAliveOnly);
        node = DockContextFindNodeByID(ctx, node_id);
    }
    else
    {
        node = DockContextAddNode(ctx, node_id);
        node->SetLocalFlags(flags);
    }
    node->LastFrameAlive = ctx->FrameCount;   // Set this otherwise BeginDocked will undock during the same frame.
    return node->ID;
}

void ImGui::DockBuilderRemoveNode(ImGuiID node_id)
{
    ImGuiContext* ctx = GImGui;
    ImGuiContext& g = *ctx; IM_UNUSED(g);
    IMGUI_DEBUG_LOG_DOCKING("[docking] DockBuilderRemoveNode 0x%08X\n", node_id);

    ImGuiDockNode* node = DockContextFindNodeByID(ctx, node_id);
    if (node == NULL)
        return;
    DockBuilderRemoveNodeDockedWindows(node_id, true);
    DockBuilderRemoveNodeChildNodes(node_id);
    // Node may have moved or deleted if e.g. any merge happened
    node = DockContextFindNodeByID(ctx, node_id);
    if (node == NULL)
        return;
    if (node->IsCentralNode() && node->ParentNode)
        node->ParentNode->SetLocalFlags(node->ParentNode->LocalFlags | ImGuiDockNodeFlags_CentralNode);
    DockContextRemoveNode(ctx, node, true);
}

// root_id = 0 to remove all, root_id != 0 to remove child of given node.
void ImGui::DockBuilderRemoveNodeChildNodes(ImGuiID root_id)
{
    ImGuiContext* ctx = GImGui;
    ImGuiDockContext* dc  = &ctx->DockContext;

    ImGuiDockNode* root_node = root_id ? DockContextFindNodeByID(ctx, root_id) : NULL;
    if (root_id && root_node == NULL)
        return;
    bool has_central_node = false;

    ImGuiDataAuthority backup_root_node_authority_for_pos = root_node ? root_node->AuthorityForPos : ImGuiDataAuthority_Auto;
    ImGuiDataAuthority backup_root_node_authority_for_size = root_node ? root_node->AuthorityForSize : ImGuiDataAuthority_Auto;

    // Process active windows
    ImVector<ImGuiDockNode*> nodes_to_remove;
    for (int n = 0; n < dc->Nodes.Data.Size; n++)
        if (ImGuiDockNode* node = (ImGuiDockNode*)dc->Nodes.Data[n].val_p)
        {
            bool want_removal = (root_id == 0) || (node->ID != root_id && DockNodeGetRootNode(node)->ID == root_id);
            if (want_removal)
            {
                if (node->IsCentralNode())
                    has_central_node = true;
                if (root_id != 0)
                    DockContextQueueNotifyRemovedNode(ctx, node);
                if (root_node)
                {
                    DockNodeMoveWindows(root_node, node);
                    DockSettingsRenameNodeReferences(node->ID, root_node->ID);
                }
                nodes_to_remove.push_back(node);
            }
        }

    // DockNodeMoveWindows->DockNodeAddWindow will normally set those when reaching two windows (which is only adequate during interactive merge)
    // Make sure we don't lose our current pos/size. (FIXME-DOCK: Consider tidying up that code in DockNodeAddWindow instead)
    if (root_node)
    {
        root_node->AuthorityForPos = backup_root_node_authority_for_pos;
        root_node->AuthorityForSize = backup_root_node_authority_for_size;
    }

    // Apply to settings
    for (ImGuiWindowSettings* settings = ctx->SettingsWindows.begin(); settings != NULL; settings = ctx->SettingsWindows.next_chunk(settings))
        if (ImGuiID window_settings_dock_id = settings->DockId)
            for (int n = 0; n < nodes_to_remove.Size; n++)
                if (nodes_to_remove[n]->ID == window_settings_dock_id)
                {
                    settings->DockId = root_id;
                    break;
                }

    // Not really efficient, but easier to destroy a whole hierarchy considering DockContextRemoveNode is attempting to merge nodes
    if (nodes_to_remove.Size > 1)
        ImQsort(nodes_to_remove.Data, nodes_to_remove.Size, sizeof(ImGuiDockNode*), DockNodeComparerDepthMostFirst);
    for (int n = 0; n < nodes_to_remove.Size; n++)
        DockContextRemoveNode(ctx, nodes_to_remove[n], false);

    if (root_id == 0)
    {
        dc->Nodes.Clear();
        dc->Requests.clear();
    }
    else if (has_central_node)
    {
        root_node->CentralNode = root_node;
        root_node->SetLocalFlags(root_node->LocalFlags | ImGuiDockNodeFlags_CentralNode);
    }
}

void ImGui::DockBuilderRemoveNodeDockedWindows(ImGuiID root_id, bool clear_settings_refs)
{
    // Clear references in settings
    ImGuiContext* ctx = GImGui;
    ImGuiContext& g = *ctx;
    if (clear_settings_refs)
    {
        for (ImGuiWindowSettings* settings = g.SettingsWindows.begin(); settings != NULL; settings = g.SettingsWindows.next_chunk(settings))
        {
            bool want_removal = (root_id == 0) || (settings->DockId == root_id);
            if (!want_removal && settings->DockId != 0)
                if (ImGuiDockNode* node = DockContextFindNodeByID(ctx, settings->DockId))
                    if (DockNodeGetRootNode(node)->ID == root_id)
                        want_removal = true;
            if (want_removal)
                settings->DockId = 0;
        }
    }

    // Clear references in windows
    for (int n = 0; n < g.Windows.Size; n++)
    {
        ImGuiWindow* window = g.Windows[n];
        bool want_removal = (root_id == 0) || (window->DockNode && DockNodeGetRootNode(window->DockNode)->ID == root_id) || (window->DockNodeAsHost && window->DockNodeAsHost->ID == root_id);
        if (want_removal)
        {
            const ImGuiID backup_dock_id = window->DockId;
            IM_UNUSED(backup_dock_id);
            DockContextProcessUndockWindow(ctx, window, clear_settings_refs);
            if (!clear_settings_refs)
                IM_ASSERT(window->DockId == backup_dock_id);
        }
    }
}

// If 'out_id_at_dir' or 'out_id_at_opposite_dir' are non NULL, the function will write out the ID of the two new nodes created.
// Return value is ID of the node at the specified direction, so same as (*out_id_at_dir) if that pointer is set.
// FIXME-DOCK: We are not exposing nor using split_outer.
ImGuiID ImGui::DockBuilderSplitNode(ImGuiID id, ImGuiDir split_dir, float size_ratio_for_node_at_dir, ImGuiID* out_id_at_dir, ImGuiID* out_id_at_opposite_dir)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(split_dir != ImGuiDir_None);
    IMGUI_DEBUG_LOG_DOCKING("[docking] DockBuilderSplitNode: node 0x%08X, split_dir %d\n", id, split_dir);

    ImGuiDockNode* node = DockContextFindNodeByID(&g, id);
    if (node == NULL)
    {
        IM_ASSERT(node != NULL);
        return 0;
    }

    IM_ASSERT(!node->IsSplitNode()); // Assert if already Split

    ImGuiDockRequest req;
    req.Type = ImGuiDockRequestType_Split;
    req.DockTargetWindow = NULL;
    req.DockTargetNode = node;
    req.DockPayload = NULL;
    req.DockSplitDir = split_dir;
    req.DockSplitRatio = ImSaturate((split_dir == ImGuiDir_Left || split_dir == ImGuiDir_Up) ? size_ratio_for_node_at_dir : 1.0f - size_ratio_for_node_at_dir);
    req.DockSplitOuter = false;
    DockContextProcessDock(&g, &req);

    ImGuiID id_at_dir = node->ChildNodes[(split_dir == ImGuiDir_Left || split_dir == ImGuiDir_Up) ? 0 : 1]->ID;
    ImGuiID id_at_opposite_dir = node->ChildNodes[(split_dir == ImGuiDir_Left || split_dir == ImGuiDir_Up) ? 1 : 0]->ID;
    if (out_id_at_dir)
        *out_id_at_dir = id_at_dir;
    if (out_id_at_opposite_dir)
        *out_id_at_opposite_dir = id_at_opposite_dir;
    return id_at_dir;
}

static ImGuiDockNode* DockBuilderCopyNodeRec(ImGuiDockNode* src_node, ImGuiID dst_node_id_if_known, ImVector<ImGuiID>* out_node_remap_pairs)
{
    ImGuiContext& g = *GImGui;
    ImGuiDockNode* dst_node = ImGui::DockContextAddNode(&g, dst_node_id_if_known);
    dst_node->SharedFlags = src_node->SharedFlags;
    dst_node->LocalFlags = src_node->LocalFlags;
    dst_node->LocalFlagsInWindows = ImGuiDockNodeFlags_None;
    dst_node->Pos = src_node->Pos;
    dst_node->Size = src_node->Size;
    dst_node->SizeRef = src_node->SizeRef;
    dst_node->SplitAxis = src_node->SplitAxis;
    dst_node->UpdateMergedFlags();

    out_node_remap_pairs->push_back(src_node->ID);
    out_node_remap_pairs->push_back(dst_node->ID);

    for (int child_n = 0; child_n < IM_ARRAYSIZE(src_node->ChildNodes); child_n++)
        if (src_node->ChildNodes[child_n])
        {
            dst_node->ChildNodes[child_n] = DockBuilderCopyNodeRec(src_node->ChildNodes[child_n], 0, out_node_remap_pairs);
            dst_node->ChildNodes[child_n]->ParentNode = dst_node;
        }

    IMGUI_DEBUG_LOG_DOCKING("[docking] Fork node %08X -> %08X (%d childs)\n", src_node->ID, dst_node->ID, dst_node->IsSplitNode() ? 2 : 0);
    return dst_node;
}

void ImGui::DockBuilderCopyNode(ImGuiID src_node_id, ImGuiID dst_node_id, ImVector<ImGuiID>* out_node_remap_pairs)
{
    ImGuiContext* ctx = GImGui;
    IM_ASSERT(src_node_id != 0);
    IM_ASSERT(dst_node_id != 0);
    IM_ASSERT(out_node_remap_pairs != NULL);

    DockBuilderRemoveNode(dst_node_id);

    ImGuiDockNode* src_node = DockContextFindNodeByID(ctx, src_node_id);
    IM_ASSERT(src_node != NULL);

    out_node_remap_pairs->clear();
    DockBuilderCopyNodeRec(src_node, dst_node_id, out_node_remap_pairs);

    IM_ASSERT((out_node_remap_pairs->Size % 2) == 0);
}

void ImGui::DockBuilderCopyWindowSettings(const char* src_name, const char* dst_name)
{
    ImGuiWindow* src_window = FindWindowByName(src_name);
    if (src_window == NULL)
        return;
    if (ImGuiWindow* dst_window = FindWindowByName(dst_name))
    {
        dst_window->Pos = src_window->Pos;
        dst_window->Size = src_window->Size;
        dst_window->SizeFull = src_window->SizeFull;
        dst_window->Collapsed = src_window->Collapsed;
    }
    else
    {
        ImGuiWindowSettings* dst_settings = FindWindowSettingsByID(ImHashStr(dst_name));
        if (!dst_settings)
            dst_settings = CreateNewWindowSettings(dst_name);
        ImVec2ih window_pos_2ih = ImVec2ih(src_window->Pos);
        if (src_window->ViewportId != 0 && src_window->ViewportId != IMGUI_VIEWPORT_DEFAULT_ID)
        {
            dst_settings->ViewportPos = window_pos_2ih;
            dst_settings->ViewportId = src_window->ViewportId;
            dst_settings->Pos = ImVec2ih(0, 0);
        }
        else
        {
            dst_settings->Pos = window_pos_2ih;
        }
        dst_settings->Size = ImVec2ih(src_window->SizeFull);
        dst_settings->Collapsed = src_window->Collapsed;
    }
}

// FIXME: Will probably want to change this signature, in particular how the window remapping pairs are passed.
void ImGui::DockBuilderCopyDockSpace(ImGuiID src_dockspace_id, ImGuiID dst_dockspace_id, ImVector<const char*>* in_window_remap_pairs)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(src_dockspace_id != 0);
    IM_ASSERT(dst_dockspace_id != 0);
    IM_ASSERT(in_window_remap_pairs != NULL);
    IM_ASSERT((in_window_remap_pairs->Size % 2) == 0);

    // Duplicate entire dock
    // FIXME: When overwriting dst_dockspace_id, windows that aren't part of our dockspace window class but that are docked in a same node will be split apart,
    // whereas we could attempt to at least keep them together in a new, same floating node.
    ImVector<ImGuiID> node_remap_pairs;
    DockBuilderCopyNode(src_dockspace_id, dst_dockspace_id, &node_remap_pairs);

    // Attempt to transition all the upcoming windows associated to dst_dockspace_id into the newly created hierarchy of dock nodes
    // (The windows associated to src_dockspace_id are staying in place)
    ImVector<ImGuiID> src_windows;
    for (int remap_window_n = 0; remap_window_n < in_window_remap_pairs->Size; remap_window_n += 2)
    {
        const char* src_window_name = (*in_window_remap_pairs)[remap_window_n];
        const char* dst_window_name = (*in_window_remap_pairs)[remap_window_n + 1];
        ImGuiID src_window_id = ImHashStr(src_window_name);
        src_windows.push_back(src_window_id);

        // Search in the remapping tables
        ImGuiID src_dock_id = 0;
        if (ImGuiWindow* src_window = FindWindowByID(src_window_id))
            src_dock_id = src_window->DockId;
        else if (ImGuiWindowSettings* src_window_settings = FindWindowSettingsByID(src_window_id))
            src_dock_id = src_window_settings->DockId;
        ImGuiID dst_dock_id = 0;
        for (int dock_remap_n = 0; dock_remap_n < node_remap_pairs.Size; dock_remap_n += 2)
            if (node_remap_pairs[dock_remap_n] == src_dock_id)
            {
                dst_dock_id = node_remap_pairs[dock_remap_n + 1];
                //node_remap_pairs[dock_remap_n] = node_remap_pairs[dock_remap_n + 1] = 0; // Clear
                break;
            }

        if (dst_dock_id != 0)
        {
            // Docked windows gets redocked into the new node hierarchy.
            IMGUI_DEBUG_LOG_DOCKING("[docking] Remap live window '%s' 0x%08X -> '%s' 0x%08X\n", src_window_name, src_dock_id, dst_window_name, dst_dock_id);
            DockBuilderDockWindow(dst_window_name, dst_dock_id);
        }
        else
        {
            // Floating windows gets their settings transferred (regardless of whether the new window already exist or not)
            // When this is leading to a Copy and not a Move, we would get two overlapping floating windows. Could we possibly dock them together?
            IMGUI_DEBUG_LOG_DOCKING("[docking] Remap window settings '%s' -> '%s'\n", src_window_name, dst_window_name);
            DockBuilderCopyWindowSettings(src_window_name, dst_window_name);
        }
    }

    // Anything else in the source nodes of 'node_remap_pairs' are windows that are not included in the remapping list.
    // Find those windows and move to them to the cloned dock node. This may be optional?
    // Dock those are a second step as undocking would invalidate source dock nodes.
    struct DockRemainingWindowTask { ImGuiWindow* Window; ImGuiID DockId; DockRemainingWindowTask(ImGuiWindow* window, ImGuiID dock_id) { Window = window; DockId = dock_id; } };
    ImVector<DockRemainingWindowTask> dock_remaining_windows;
    for (int dock_remap_n = 0; dock_remap_n < node_remap_pairs.Size; dock_remap_n += 2)
        if (ImGuiID src_dock_id = node_remap_pairs[dock_remap_n])
        {
            ImGuiID dst_dock_id = node_remap_pairs[dock_remap_n + 1];
            ImGuiDockNode* node = DockBuilderGetNode(src_dock_id);
            for (int window_n = 0; window_n < node->Windows.Size; window_n++)
            {
                ImGuiWindow* window = node->Windows[window_n];
                if (src_windows.contains(window->ID))
                    continue;

                // Docked windows gets redocked into the new node hierarchy.
                IMGUI_DEBUG_LOG_DOCKING("[docking] Remap window '%s' %08X -> %08X\n", window->Name, src_dock_id, dst_dock_id);
                dock_remaining_windows.push_back(DockRemainingWindowTask(window, dst_dock_id));
            }
        }
    for (const DockRemainingWindowTask& task : dock_remaining_windows)
        DockBuilderDockWindow(task.Window->Name, task.DockId);
}

// FIXME-DOCK: This is awkward because in series of split user is likely to loose access to its root node.
void ImGui::DockBuilderFinish(ImGuiID root_id)
{
    ImGuiContext* ctx = GImGui;
    //DockContextRebuild(ctx);
    DockContextBuildAddWindowsToNodes(ctx, root_id);
}

//-----------------------------------------------------------------------------
// Docking: Begin/End Support Functions (called from Begin/End)
//-----------------------------------------------------------------------------
// - GetWindowAlwaysWantOwnTabBar()
// - DockContextBindNodeToWindow()
// - BeginDocked()
// - BeginDockableDragDropSource()
// - BeginDockableDragDropTarget()
//-----------------------------------------------------------------------------

bool ImGui::GetWindowAlwaysWantOwnTabBar(ImGuiWindow* window)
{
    ImGuiContext& g = *GImGui;
    if (g.IO.ConfigDockingAlwaysTabBar || window->WindowClass.DockingAlwaysTabBar)
        if ((window->Flags & (ImGuiWindowFlags_ChildWindow | ImGuiWindowFlags_NoTitleBar | ImGuiWindowFlags_NoDocking)) == 0)
            if (!window->IsFallbackWindow)    // We don't support AlwaysTabBar on the fallback/implicit window to avoid unused dock-node overhead/noise
                return true;
    return false;
}

static ImGuiDockNode* ImGui::DockContextBindNodeToWindow(ImGuiContext* ctx, ImGuiWindow* window)
{
    ImGuiContext& g = *ctx;
    ImGuiDockNode* node = DockContextFindNodeByID(ctx, window->DockId);
    IM_ASSERT(window->DockNode == NULL);

    // We should not be docking into a split node (SetWindowDock should avoid this)
    if (node && node->IsSplitNode())
    {
        DockContextProcessUndockWindow(ctx, window);
        return NULL;
    }

    // Create node
    if (node == NULL)
    {
        node = DockContextAddNode(ctx, window->DockId);
        node->AuthorityForPos = node->AuthorityForSize = node->AuthorityForViewport = ImGuiDataAuthority_Window;
        node->LastFrameAlive = g.FrameCount;
    }

    // If the node just turned visible and is part of a hierarchy, it doesn't have a Size assigned by DockNodeTreeUpdatePosSize() yet,
    // so we're forcing a Pos/Size update from the first ancestor that is already visible (often it will be the root node).
    // If we don't do this, the window will be assigned a zero-size on its first frame, which won't ideally warm up the layout.
    // This is a little wonky because we don't normally update the Pos/Size of visible node mid-frame.
    if (!node->IsVisible)
    {
        ImGuiDockNode* ancestor_node = node;
        while (!ancestor_node->IsVisible && ancestor_node->ParentNode)
            ancestor_node = ancestor_node->ParentNode;
        IM_ASSERT(ancestor_node->Size.x > 0.0f && ancestor_node->Size.y > 0.0f);
        DockNodeUpdateHasCentralNodeChild(DockNodeGetRootNode(ancestor_node));
        DockNodeTreeUpdatePosSize(ancestor_node, ancestor_node->Pos, ancestor_node->Size, node);
    }

    // Add window to node
    bool node_was_visible = node->IsVisible;
    DockNodeAddWindow(node, window, true);
    node->IsVisible = node_was_visible; // Don't mark visible right away (so DockContextEndFrame() doesn't render it, maybe other side effects? will see)
    IM_ASSERT(node == window->DockNode);
    return node;
}

void ImGui::BeginDocked(ImGuiWindow* window, bool* p_open)
{
    ImGuiContext* ctx = GImGui;
    ImGuiContext& g = *ctx;

    // Clear fields ahead so most early-out paths don't have to do it
    window->DockIsActive = window->DockNodeIsVisible = window->DockTabIsVisible = false;

    const bool auto_dock_node = GetWindowAlwaysWantOwnTabBar(window);
    if (auto_dock_node)
    {
        if (window->DockId == 0)
        {
            IM_ASSERT(window->DockNode == NULL);
            window->DockId = DockContextGenNodeID(ctx);
        }
    }
    else
    {
        // Calling SetNextWindowPos() undock windows by default (by setting PosUndock)
        bool want_undock = false;
        want_undock |= (window->Flags & ImGuiWindowFlags_NoDocking) != 0;
        want_undock |= (g.NextWindowData.Flags & ImGuiNextWindowDataFlags_HasPos) && (window->SetWindowPosAllowFlags & g.NextWindowData.PosCond) && g.NextWindowData.PosUndock;
        if (want_undock)
        {
            DockContextProcessUndockWindow(ctx, window);
            return;
        }
    }

    // Bind to our dock node
    ImGuiDockNode* node = window->DockNode;
    if (node != NULL)
        IM_ASSERT(window->DockId == node->ID);
    if (window->DockId != 0 && node == NULL)
    {
        node = DockContextBindNodeToWindow(ctx, window);
        if (node == NULL)
            return;
    }

#if 0
    // Undock if the ImGuiDockNodeFlags_NoDockingInCentralNode got set
    if (node->IsCentralNode && (node->Flags & ImGuiDockNodeFlags_NoDockingInCentralNode))
    {
        DockContextProcessUndockWindow(ctx, window);
        return;
    }
#endif

    // Undock if our dockspace node disappeared
    // Note how we are testing for LastFrameAlive and NOT LastFrameActive. A DockSpace node can be maintained alive while being inactive with ImGuiDockNodeFlags_KeepAliveOnly.
    if (node->LastFrameAlive < g.FrameCount)
    {
        // If the window has been orphaned, transition the docknode to an implicit node processed in DockContextNewFrameUpdateDocking()
        ImGuiDockNode* root_node = DockNodeGetRootNode(node);
        if (root_node->LastFrameAlive < g.FrameCount)
            DockContextProcessUndockWindow(ctx, window);
        else
            window->DockIsActive = true;
        return;
    }

    // Store style overrides
    for (int color_n = 0; color_n < ImGuiWindowDockStyleCol_COUNT; color_n++)
        window->DockStyle.Colors[color_n] = ColorConvertFloat4ToU32(g.Style.Colors[GWindowDockStyleColors[color_n]]);

    // Fast path return. It is common for windows to hold on a persistent DockId but be the only visible window,
    // and never create neither a host window neither a tab bar.
    // FIXME-DOCK: replace ->HostWindow NULL compare with something more explicit (~was initially intended as a first frame test)
    if (node->HostWindow == NULL)
    {
        if (node->State == ImGuiDockNodeState_HostWindowHiddenBecauseWindowsAreResizing)
            window->DockIsActive = true;
        if (node->Windows.Size > 1 && window->Appearing) // Only hide appearing window
            DockNodeHideWindowDuringHostWindowCreation(window);
        return;
    }

    // We can have zero-sized nodes (e.g. children of a small-size dockspace)
    IM_ASSERT(node->HostWindow);
    IM_ASSERT(node->IsLeafNode());
    IM_ASSERT(node->Size.x >= 0.0f && node->Size.y >= 0.0f);
    node->State = ImGuiDockNodeState_HostWindowVisible;

    // Undock if we are submitted earlier than the host window
    if (!(node->MergedFlags & ImGuiDockNodeFlags_KeepAliveOnly) && window->BeginOrderWithinContext < node->HostWindow->BeginOrderWithinContext)
    {
        DockContextProcessUndockWindow(ctx, window);
        return;
    }

    // Position/Size window
    SetNextWindowPos(node->Pos);
    SetNextWindowSize(node->Size);
    g.NextWindowData.PosUndock = false; // Cancel implicit undocking of SetNextWindowPos()
    window->DockIsActive = true;
    window->DockNodeIsVisible = true;
    window->DockTabIsVisible = false;
    if (node->MergedFlags & ImGuiDockNodeFlags_KeepAliveOnly)
        return;

    // When the window is selected we mark it as visible.
    if (node->VisibleWindow == window)
        window->DockTabIsVisible = true;

    // Update window flag
    IM_ASSERT((window->Flags & ImGuiWindowFlags_ChildWindow) == 0);
    window->Flags |= ImGuiWindowFlags_ChildWindow | ImGuiWindowFlags_NoResize;
    window->ChildFlags |= ImGuiChildFlags_AlwaysUseWindowPadding;
    if (node->IsHiddenTabBar() || node->IsNoTabBar())
        window->Flags |= ImGuiWindowFlags_NoTitleBar;
    else
        window->Flags &= ~ImGuiWindowFlags_NoTitleBar;      // Clear the NoTitleBar flag in case the user set it: confusingly enough we need a title bar height so we are correctly offset, but it won't be displayed!

    // Save new dock order only if the window has been visible once already
    // This allows multiple windows to be created in the same frame and have their respective dock orders preserved.
    if (node->TabBar && window->WasActive)
        window->DockOrder = (short)DockNodeGetTabOrder(window);

    if ((node->WantCloseAll || node->WantCloseTabId == window->TabId) && p_open != NULL)
        *p_open = false;

    // Update ChildId to allow returning from Child to Parent with Escape
    ImGuiWindow* parent_window = window->DockNode->HostWindow;
    window->ChildId = parent_window->GetID(window->Name);
}

void ImGui::BeginDockableDragDropSource(ImGuiWindow* window)
{
    ImGuiContext& g = *GImGui;
    IM_ASSERT(g.ActiveId == window->MoveId);
    IM_ASSERT(g.MovingWindow == window);
    IM_ASSERT(g.CurrentWindow == window);

    // 0: Hold SHIFT to disable docking, 1: Hold SHIFT to enable docking.
    if (g.IO.ConfigDockingWithShift != g.IO.KeyShift)
    {
        // When ConfigDockingWithShift is set, display a tooltip to increase UI affordance.
        // We cannot set for HoveredWindowUnderMovingWindow != NULL here, as it is only valid/useful when drag and drop is already active
        // (because of the 'is_mouse_dragging_with_an_expected_destination' logic in UpdateViewportsNewFrame() function)
        if (g.IO.ConfigDockingWithShift && g.MouseStationaryTimer >= 1.0f && g.ActiveId >= 1.0f)
            SetTooltip("%s", LocalizeGetMsg(ImGuiLocKey_DockingHoldShiftToDock));
        return;
    }

    g.LastItemData.ID = window->MoveId;
    window = window->RootWindowDockTree;
    IM_ASSERT((window->Flags & ImGuiWindowFlags_NoDocking) == 0);
    bool is_drag_docking = (g.IO.ConfigDockingWithShift) || ImRect(0, 0, window->SizeFull.x, GetFrameHeight()).Contains(g.ActiveIdClickOffset); // FIXME-DOCKING: Need to make this stateful and explicit
    if (is_drag_docking && BeginDragDropSource(ImGuiDragDropFlags_SourceNoPreviewTooltip | ImGuiDragDropFlags_SourceNoHoldToOpenOthers | ImGuiDragDropFlags_SourceAutoExpirePayload))
    {
        SetDragDropPayload(IMGUI_PAYLOAD_TYPE_WINDOW, &window, sizeof(window));
        EndDragDropSource();

        // Store style overrides
        for (int color_n = 0; color_n < ImGuiWindowDockStyleCol_COUNT; color_n++)
            window->DockStyle.Colors[color_n] = ColorConvertFloat4ToU32(g.Style.Colors[GWindowDockStyleColors[color_n]]);
    }
}

void ImGui::BeginDockableDragDropTarget(ImGuiWindow* window)
{
    ImGuiContext* ctx = GImGui;
    ImGuiContext& g = *ctx;

    //IM_ASSERT(window->RootWindowDockTree == window); // May also be a DockSpace
    IM_ASSERT((window->Flags & ImGuiWindowFlags_NoDocking) == 0);
    if (!g.DragDropActive)
        return;
    //GetForegroundDrawList(window)->AddRect(window->Pos, window->Pos + window->Size, IM_COL32(255, 255, 0, 255));
    if (!BeginDragDropTargetCustom(window->Rect(), window->ID))
        return;

    // Peek into the payload before calling AcceptDragDropPayload() so we can handle overlapping dock nodes with filtering
    // (this is a little unusual pattern, normally most code would call AcceptDragDropPayload directly)
    const ImGuiPayload* payload = &g.DragDropPayload;
    if (!payload->IsDataType(IMGUI_PAYLOAD_TYPE_WINDOW) || !DockNodeIsDropAllowed(window, *(ImGuiWindow**)payload->Data))
    {
        EndDragDropTarget();
        return;
    }

    ImGuiWindow* payload_window = *(ImGuiWindow**)payload->Data;
    if (AcceptDragDropPayload(IMGUI_PAYLOAD_TYPE_WINDOW, ImGuiDragDropFlags_AcceptBeforeDelivery | ImGuiDragDropFlags_AcceptNoDrawDefaultRect))
    {
        // Select target node
        // (Important: we cannot use g.HoveredDockNode here! Because each of our target node have filters based on payload, each candidate drop target will do its own evaluation)
        bool dock_into_floating_window = false;
        ImGuiDockNode* node = NULL;
        if (window->DockNodeAsHost)
        {
            // Cannot assume that node will != NULL even though we passed the rectangle test: it depends on padding/spacing handled by DockNodeTreeFindVisibleNodeByPos().
            node = DockNodeTreeFindVisibleNodeByPos(window->DockNodeAsHost, g.IO.MousePos);

            // There is an edge case when docking into a dockspace which only has _inactive_ nodes (because none of the windows are active)
            // In this case we need to fallback into any leaf mode, possibly the central node.
            // FIXME-20181220: We should not have to test for IsLeafNode() here but we have another bug to fix first.
            if (node && node->IsDockSpace() && node->IsRootNode())
                node = (node->CentralNode && node->IsLeafNode()) ? node->CentralNode : DockNodeTreeFindFallbackLeafNode(node);
        }
        else
        {
            if (window->DockNode)
                node = window->DockNode;
            else
                dock_into_floating_window = true; // Dock into a regular window
        }

        const ImRect explicit_target_rect = (node && node->TabBar && !node->IsHiddenTabBar() && !node->IsNoTabBar()) ? node->TabBar->BarRect : ImRect(window->Pos, window->Pos + ImVec2(window->Size.x, GetFrameHeight()));
        const bool is_explicit_target = g.IO.ConfigDockingWithShift || IsMouseHoveringRect(explicit_target_rect.Min, explicit_target_rect.Max);

        // Preview docking request and find out split direction/ratio
        //const bool do_preview = true;     // Ignore testing for payload->IsPreview() which removes one frame of delay, but breaks overlapping drop targets within the same window.
        const bool do_preview = payload->IsPreview() || payload->IsDelivery();
        if (do_preview && (node != NULL || dock_into_floating_window))
        {
            // If we have a non-leaf node it means we are hovering the border of a parent node, in which case only outer markers will appear.
            ImGuiDockPreviewData split_inner;
            ImGuiDockPreviewData split_outer;
            ImGuiDockPreviewData* split_data = &split_inner;
            if (node && (node->ParentNode || node->IsCentralNode() || !node->IsLeafNode()))
                if (ImGuiDockNode* root_node = DockNodeGetRootNode(node))
                {
                    DockNodePreviewDockSetup(window, root_node, payload_window, NULL, &split_outer, is_explicit_target, true);
                    if (split_outer.IsSplitDirExplicit)
                        split_data = &split_outer;
                }
            if (!node || node->IsLeafNode())
                DockNodePreviewDockSetup(window, node, payload_window, NULL, &split_inner, is_explicit_target, false);
            if (split_data == &split_outer)
                split_inner.IsDropAllowed = false;

            // Draw inner then outer, so that previewed tab (in inner data) will be behind the outer drop boxes
            DockNodePreviewDockRender(window, node, payload_window, &split_inner);
            DockNodePreviewDockRender(window, node, payload_window, &split_outer);

            // Queue docking request
            if (split_data->IsDropAllowed && payload->IsDelivery())
                DockContextQueueDock(ctx, window, split_data->SplitNode, payload_window, split_data->SplitDir, split_data->SplitRatio, split_data == &split_outer);
        }
    }
    EndDragDropTarget();
}

//-----------------------------------------------------------------------------
// Docking: Settings
//-----------------------------------------------------------------------------
// - DockSettingsRenameNodeReferences()
// - DockSettingsRemoveNodeReferences()
// - DockSettingsFindNodeSettings()
// - DockSettingsHandler_ApplyAll()
// - DockSettingsHandler_ReadOpen()
// - DockSettingsHandler_ReadLine()
// - DockSettingsHandler_DockNodeToSettings()
// - DockSettingsHandler_WriteAll()
//-----------------------------------------------------------------------------

static void ImGui::DockSettingsRenameNodeReferences(ImGuiID old_node_id, ImGuiID new_node_id)
{
    ImGuiContext& g = *GImGui;
    IMGUI_DEBUG_LOG_DOCKING("[docking] DockSettingsRenameNodeReferences: from 0x%08X -> to 0x%08X\n", old_node_id, new_node_id);
    for (int window_n = 0; window_n < g.Windows.Size; window_n++)
    {
        ImGuiWindow* window = g.Windows[window_n];
        if (window->DockId == old_node_id && window->DockNode == NULL)
            window->DockId = new_node_id;
    }
    //// FIXME-OPT: We could remove this loop by storing the index in the map
    for (ImGuiWindowSettings* settings = g.SettingsWindows.begin(); settings != NULL; settings = g.SettingsWindows.next_chunk(settings))
        if (settings->DockId == old_node_id)
            settings->DockId = new_node_id;
}

// Remove references stored in ImGuiWindowSettings to the given ImGuiDockNodeSettings
static void ImGui::DockSettingsRemoveNodeReferences(ImGuiID* node_ids, int node_ids_count)
{
    ImGuiContext& g = *GImGui;
    int found = 0;
    //// FIXME-OPT: We could remove this loop by storing the index in the map
    for (ImGuiWindowSettings* settings = g.SettingsWindows.begin(); settings != NULL; settings = g.SettingsWindows.next_chunk(settings))
        for (int node_n = 0; node_n < node_ids_count; node_n++)
            if (settings->DockId == node_ids[node_n])
            {
                settings->DockId = 0;
                settings->DockOrder = -1;
                if (++found < node_ids_count)
                    break;
                return;
            }
}

static ImGuiDockNodeSettings* ImGui::DockSettingsFindNodeSettings(ImGuiContext* ctx, ImGuiID id)
{
    // FIXME-OPT
    ImGuiDockContext* dc  = &ctx->DockContext;
    for (int n = 0; n < dc->NodesSettings.Size; n++)
        if (dc->NodesSettings[n].ID == id)
            return &dc->NodesSettings[n];
    return NULL;
}

// Clear settings data
static void ImGui::DockSettingsHandler_ClearAll(ImGuiContext* ctx, ImGuiSettingsHandler*)
{
    ImGuiDockContext* dc  = &ctx->DockContext;
    dc->NodesSettings.clear();
    DockContextClearNodes(ctx, 0, true);
}

// Recreate nodes based on settings data
static void ImGui::DockSettingsHandler_ApplyAll(ImGuiContext* ctx, ImGuiSettingsHandler*)
{
    // Prune settings at boot time only
    ImGuiDockContext* dc  = &ctx->DockContext;
    if (ctx->Windows.Size == 0)
        DockContextPruneUnusedSettingsNodes(ctx);
    DockContextBuildNodesFromSettings(ctx, dc->NodesSettings.Data, dc->NodesSettings.Size);
    DockContextBuildAddWindowsToNodes(ctx, 0);
}

static void* ImGui::DockSettingsHandler_ReadOpen(ImGuiContext*, ImGuiSettingsHandler*, const char* name)
{
    if (strcmp(name, "Data") != 0)
        return NULL;
    return (void*)1;
}

static void ImGui::DockSettingsHandler_ReadLine(ImGuiContext* ctx, ImGuiSettingsHandler*, void*, const char* line)
{
    char c = 0;
    int x = 0, y = 0;
    int r = 0;

    // Parsing, e.g.
    // " DockNode   ID=0x00000001 Pos=383,193 Size=201,322 Split=Y,0.506 "
    // "   DockNode ID=0x00000002 Parent=0x00000001 "
    // Important: this code expect currently fields in a fixed order.
    ImGuiDockNodeSettings node;
    line = ImStrSkipBlank(line);
    if      (strncmp(line, "DockNode", 8) == 0)  { line = ImStrSkipBlank(line + strlen("DockNode")); }
    else if (strncmp(line, "DockSpace", 9) == 0) { line = ImStrSkipBlank(line + strlen("DockSpace")); node.Flags |= ImGuiDockNodeFlags_DockSpace; }
    else return;
    if (sscanf(line, "ID=0x%08X%n",      &node.ID, &r) == 1)            { line += r; } else return;
    if (sscanf(line, " Parent=0x%08X%n", &node.ParentNodeId, &r) == 1)  { line += r; if (node.ParentNodeId == 0) return; }
    if (sscanf(line, " Window=0x%08X%n", &node.ParentWindowId, &r) ==1) { line += r; if (node.ParentWindowId == 0) return; }
    if (node.ParentNodeId == 0)
    {
        if (sscanf(line, " Pos=%i,%i%n",  &x, &y, &r) == 2)         { line += r; node.Pos = ImVec2ih((short)x, (short)y); } else return;
        if (sscanf(line, " Size=%i,%i%n", &x, &y, &r) == 2)         { line += r; node.Size = ImVec2ih((short)x, (short)y); } else return;
    }
    else
    {
        if (sscanf(line, " SizeRef=%i,%i%n", &x, &y, &r) == 2)      { line += r; node.SizeRef = ImVec2ih((short)x, (short)y); }
    }
    if (sscanf(line, " Split=%c%n", &c, &r) == 1)                   { line += r; if (c == 'X') node.SplitAxis = ImGuiAxis_X; else if (c == 'Y') node.SplitAxis = ImGuiAxis_Y; }
    if (sscanf(line, " NoResize=%d%n", &x, &r) == 1)                { line += r; if (x != 0) node.Flags |= ImGuiDockNodeFlags_NoResize; }
    if (sscanf(line, " CentralNode=%d%n", &x, &r) == 1)             { line += r; if (x != 0) node.Flags |= ImGuiDockNodeFlags_CentralNode; }
    if (sscanf(line, " NoTabBar=%d%n", &x, &r) == 1)                { line += r; if (x != 0) node.Flags |= ImGuiDockNodeFlags_NoTabBar; }
    if (sscanf(line, " HiddenTabBar=%d%n", &x, &r) == 1)            { line += r; if (x != 0) node.Flags |= ImGuiDockNodeFlags_HiddenTabBar; }
    if (sscanf(line, " NoWindowMenuButton=%d%n", &x, &r) == 1)      { line += r; if (x != 0) node.Flags |= ImGuiDockNodeFlags_NoWindowMenuButton; }
    if (sscanf(line, " NoCloseButton=%d%n", &x, &r) == 1)           { line += r; if (x != 0) node.Flags |= ImGuiDockNodeFlags_NoCloseButton; }
    if (sscanf(line, " Selected=0x%08X%n", &node.SelectedTabId,&r) == 1) { line += r; }
    if (node.ParentNodeId != 0)
        if (ImGuiDockNodeSettings* parent_settings = DockSettingsFindNodeSettings(ctx, node.ParentNodeId))
            node.Depth = parent_settings->Depth + 1;
    ctx->DockContext.NodesSettings.push_back(node);
}

static void DockSettingsHandler_DockNodeToSettings(ImGuiDockContext* dc, ImGuiDockNode* node, int depth)
{
    ImGuiDockNodeSettings node_settings;
    IM_ASSERT(depth < (1 << (sizeof(node_settings.Depth) << 3)));
    node_settings.ID = node->ID;
    node_settings.ParentNodeId = node->ParentNode ? node->ParentNode->ID : 0;
    node_settings.ParentWindowId = (node->IsDockSpace() && node->HostWindow && node->HostWindow->ParentWindow) ? node->HostWindow->ParentWindow->ID : 0;
    node_settings.SelectedTabId = node->SelectedTabId;
    node_settings.SplitAxis = (signed char)(node->IsSplitNode() ? node->SplitAxis : ImGuiAxis_None);
    node_settings.Depth = (char)depth;
    node_settings.Flags = (node->LocalFlags & ImGuiDockNodeFlags_SavedFlagsMask_);
    node_settings.Pos = ImVec2ih(node->Pos);
    node_settings.Size = ImVec2ih(node->Size);
    node_settings.SizeRef = ImVec2ih(node->SizeRef);
    dc->NodesSettings.push_back(node_settings);
    if (node->ChildNodes[0])
        DockSettingsHandler_DockNodeToSettings(dc, node->ChildNodes[0], depth + 1);
    if (node->ChildNodes[1])
        DockSettingsHandler_DockNodeToSettings(dc, node->ChildNodes[1], depth + 1);
}

static void ImGui::DockSettingsHandler_WriteAll(ImGuiContext* ctx, ImGuiSettingsHandler* handler, ImGuiTextBuffer* buf)
{
    ImGuiContext& g = *ctx;
    ImGuiDockContext* dc = &ctx->DockContext;
    if (!(g.IO.ConfigFlags & ImGuiConfigFlags_DockingEnable))
        return;

    // Gather settings data
    // (unlike our windows settings, because nodes are always built we can do a full rewrite of the SettingsNode buffer)
    dc->NodesSettings.resize(0);
    dc->NodesSettings.reserve(dc->Nodes.Data.Size);
    for (int n = 0; n < dc->Nodes.Data.Size; n++)
        if (ImGuiDockNode* node = (ImGuiDockNode*)dc->Nodes.Data[n].val_p)
            if (node->IsRootNode())
                DockSettingsHandler_DockNodeToSettings(dc, node, 0);

    int max_depth = 0;
    for (int node_n = 0; node_n < dc->NodesSettings.Size; node_n++)
        max_depth = ImMax((int)dc->NodesSettings[node_n].Depth, max_depth);

    // Write to text buffer
    buf->appendf("[%s][Data]\n", handler->TypeName);
    for (int node_n = 0; node_n < dc->NodesSettings.Size; node_n++)
    {
        const int line_start_pos = buf->size(); (void)line_start_pos;
        const ImGuiDockNodeSettings* node_settings = &dc->NodesSettings[node_n];
        buf->appendf("%*s%s%*s", node_settings->Depth * 2, "", (node_settings->Flags & ImGuiDockNodeFlags_DockSpace) ? "DockSpace" : "DockNode ", (max_depth - node_settings->Depth) * 2, "");  // Text align nodes to facilitate looking at .ini file
        buf->appendf(" ID=0x%08X", node_settings->ID);
        if (node_settings->ParentNodeId)
        {
            buf->appendf(" Parent=0x%08X SizeRef=%d,%d", node_settings->ParentNodeId, node_settings->SizeRef.x, node_settings->SizeRef.y);
        }
        else
        {
            if (node_settings->ParentWindowId)
                buf->appendf(" Window=0x%08X", node_settings->ParentWindowId);
            buf->appendf(" Pos=%d,%d Size=%d,%d", node_settings->Pos.x, node_settings->Pos.y, node_settings->Size.x, node_settings->Size.y);
        }
        if (node_settings->SplitAxis != ImGuiAxis_None)
            buf->appendf(" Split=%c", (node_settings->SplitAxis == ImGuiAxis_X) ? 'X' : 'Y');
        if (node_settings->Flags & ImGuiDockNodeFlags_NoResize)
            buf->appendf(" NoResize=1");
        if (node_settings->Flags & ImGuiDockNodeFlags_CentralNode)
            buf->appendf(" CentralNode=1");
        if (node_settings->Flags & ImGuiDockNodeFlags_NoTabBar)
            buf->appendf(" NoTabBar=1");
        if (node_settings->Flags & ImGuiDockNodeFlags_HiddenTabBar)
            buf->appendf(" HiddenTabBar=1");
        if (node_settings->Flags & ImGuiDockNodeFlags_NoWindowMenuButton)
            buf->appendf(" NoWindowMenuButton=1");
        if (node_settings->Flags & ImGuiDockNodeFlags_NoCloseButton)
            buf->appendf(" NoCloseButton=1");
        if (node_settings->SelectedTabId)
            buf->appendf(" Selected=0x%08X", node_settings->SelectedTabId);

        // [DEBUG] Include comments in the .ini file to ease debugging (this makes saving slower!)
        if (g.IO.ConfigDebugIniSettings)
            if (ImGuiDockNode* node = DockContextFindNodeByID(ctx, node_settings->ID))
            {
                buf->appendf("%*s", ImMax(2, (line_start_pos + 92) - buf->size()), "");     // Align everything
                if (node->IsDockSpace() && node->HostWindow && node->HostWindow->ParentWindow)
                    buf->appendf(" ; in '%s'", node->HostWindow->ParentWindow->Name);
                // Iterate settings so we can give info about windows that didn't exist during the session.
                int contains_window = 0;
                for (ImGuiWindowSettings* settings = g.SettingsWindows.begin(); settings != NULL; settings = g.SettingsWindows.next_chunk(settings))
                    if (settings->DockId == node_settings->ID)
                    {
                        if (contains_window++ == 0)
                            buf->appendf(" ; contains ");
                        buf->appendf("'%s' ", settings->GetName());
                    }
            }

        buf->appendf("\n");
    }
    buf->appendf("\n");
}


//-----------------------------------------------------------------------------
// [SECTION] PLATFORM DEPENDENT HELPERS
//-----------------------------------------------------------------------------

#if defined(_WIN32) && !defined(IMGUI_DISABLE_WIN32_FUNCTIONS) && !defined(IMGUI_DISABLE_WIN32_DEFAULT_CLIPBOARD_FUNCTIONS)

#ifdef _MSC_VER
#pragma comment(lib, "user32")
#pragma comment(lib, "kernel32")
#endif

// Win32 clipboard implementation
// We use g.ClipboardHandlerData for temporary storage to ensure it is freed on Shutdown()
static const char* GetClipboardTextFn_DefaultImpl(void* user_data_ctx)
{
    ImGuiContext& g = *(ImGuiContext*)user_data_ctx;
    g.ClipboardHandlerData.clear();
    if (!::OpenClipboard(NULL))
        return NULL;
    HANDLE wbuf_handle = ::GetClipboardData(CF_UNICODETEXT);
    if (wbuf_handle == NULL)
    {
        ::CloseClipboard();
        return NULL;
    }
    if (const WCHAR* wbuf_global = (const WCHAR*)::GlobalLock(wbuf_handle))
    {
        int buf_len = ::WideCharToMultiByte(CP_UTF8, 0, wbuf_global, -1, NULL, 0, NULL, NULL);
        g.ClipboardHandlerData.resize(buf_len);
        ::WideCharToMultiByte(CP_UTF8, 0, wbuf_global, -1, g.ClipboardHandlerData.Data, buf_len, NULL, NULL);
    }
    ::GlobalUnlock(wbuf_handle);
    ::CloseClipboard();
    return g.ClipboardHandlerData.Data;
}

static void SetClipboardTextFn_DefaultImpl(void*, const char* text)
{
    if (!::OpenClipboard(NULL))
        return;
    const int wbuf_length = ::MultiByteToWideChar(CP_UTF8, 0, text, -1, NULL, 0);
    HGLOBAL wbuf_handle = ::GlobalAlloc(GMEM_MOVEABLE, (SIZE_T)wbuf_length * sizeof(WCHAR));
    if (wbuf_handle == NULL)
    {
        ::CloseClipboard();
        return;
    }
    WCHAR* wbuf_global = (WCHAR*)::GlobalLock(wbuf_handle);
    ::MultiByteToWideChar(CP_UTF8, 0, text, -1, wbuf_global, wbuf_length);
    ::GlobalUnlock(wbuf_handle);
    ::EmptyClipboard();
    if (::SetClipboardData(CF_UNICODETEXT, wbuf_handle) == NULL)
        ::GlobalFree(wbuf_handle);
    ::CloseClipboard();
}

#elif defined(__APPLE__) && TARGET_OS_OSX && defined(IMGUI_ENABLE_OSX_DEFAULT_CLIPBOARD_FUNCTIONS)

#include <Carbon/Carbon.h>  // Use old API to avoid need for separate .mm file
static PasteboardRef main_clipboard = 0;

// OSX clipboard implementation
// If you enable this you will need to add '-framework ApplicationServices' to your linker command-line!
static void SetClipboardTextFn_DefaultImpl(void*, const char* text)
{
    if (!main_clipboard)
        PasteboardCreate(kPasteboardClipboard, &main_clipboard);
    PasteboardClear(main_clipboard);
    CFDataRef cf_data = CFDataCreate(kCFAllocatorDefault, (const UInt8*)text, strlen(text));
    if (cf_data)
    {
        PasteboardPutItemFlavor(main_clipboard, (PasteboardItemID)1, CFSTR("public.utf8-plain-text"), cf_data, 0);
        CFRelease(cf_data);
    }
}

static const char* GetClipboardTextFn_DefaultImpl(void* user_data_ctx)
{
    ImGuiContext& g = *(ImGuiContext*)user_data_ctx;
    if (!main_clipboard)
        PasteboardCreate(kPasteboardClipboard, &main_clipboard);
    PasteboardSynchronize(main_clipboard);

    ItemCount item_count = 0;
    PasteboardGetItemCount(main_clipboard, &item_count);
    for (ItemCount i = 0; i < item_count; i++)
    {
        PasteboardItemID item_id = 0;
        PasteboardGetItemIdentifier(main_clipboard, i + 1, &item_id);
        CFArrayRef flavor_type_array = 0;
        PasteboardCopyItemFlavors(main_clipboard, item_id, &flavor_type_array);
        for (CFIndex j = 0, nj = CFArrayGetCount(flavor_type_array); j < nj; j++)
        {
            CFDataRef cf_data;
            if (PasteboardCopyItemFlavorData(main_clipboard, item_id, CFSTR("public.utf8-plain-text"), &cf_data) == noErr)
            {
                g.ClipboardHandlerData.clear();
                int length = (int)CFDataGetLength(cf_data);
                g.ClipboardHandlerData.resize(length + 1);
                CFDataGetBytes(cf_data, CFRangeMake(0, length), (UInt8*)g.ClipboardHandlerData.Data);
                g.ClipboardHandlerData[length] = 0;
                CFRelease(cf_data);
                return g.ClipboardHandlerData.Data;
            }
        }
    }
    return NULL;
}

#else

// Local Dear ImGui-only clipboard implementation, if user hasn't defined better clipboard handlers.
static const char* GetClipboardTextFn_DefaultImpl(void* user_data_ctx)
{
    ImGuiContext& g = *(ImGuiContext*)user_data_ctx;
    return g.ClipboardHandlerData.empty() ? NULL : g.ClipboardHandlerData.begin();
}

static void SetClipboardTextFn_DefaultImpl(void* user_data_ctx, const char* text)
{
    ImGuiContext& g = *(ImGuiContext*)user_data_ctx;
    g.ClipboardHandlerData.clear();
    const char* text_end = text + strlen(text);
    g.ClipboardHandlerData.resize((int)(text_end - text) + 1);
    memcpy(&g.ClipboardHandlerData[0], text, (size_t)(text_end - text));
    g.ClipboardHandlerData[(int)(text_end - text)] = 0;
}

#endif

// Win32 API IME support (for Asian languages, etc.)
#if defined(_WIN32) && !defined(IMGUI_DISABLE_WIN32_FUNCTIONS) && !defined(IMGUI_DISABLE_WIN32_DEFAULT_IME_FUNCTIONS)

#include <imm.h>
#ifdef _MSC_VER
#pragma comment(lib, "imm32")
#endif

static void SetPlatformImeDataFn_DefaultImpl(ImGuiViewport* viewport, ImGuiPlatformImeData* data)
{
    // Notify OS Input Method Editor of text input position
    HWND hwnd = (HWND)viewport->PlatformHandleRaw;
    if (hwnd == 0)
        return;

    //::ImmAssociateContextEx(hwnd, NULL, data->WantVisible ? IACE_DEFAULT : 0);
    if (HIMC himc = ::ImmGetContext(hwnd))
    {
        COMPOSITIONFORM composition_form = {};
        composition_form.ptCurrentPos.x = (LONG)(data->InputPos.x - viewport->Pos.x);
        composition_form.ptCurrentPos.y = (LONG)(data->InputPos.y - viewport->Pos.y);
        composition_form.dwStyle = CFS_FORCE_POSITION;
        ::ImmSetCompositionWindow(himc, &composition_form);
        CANDIDATEFORM candidate_form = {};
        candidate_form.dwStyle = CFS_CANDIDATEPOS;
        candidate_form.ptCurrentPos.x = (LONG)(data->InputPos.x - viewport->Pos.x);
        candidate_form.ptCurrentPos.y = (LONG)(data->InputPos.y - viewport->Pos.y);
        ::ImmSetCandidateWindow(himc, &candidate_form);
        ::ImmReleaseContext(hwnd, himc);
    }
}

#else

static void SetPlatformImeDataFn_DefaultImpl(ImGuiViewport*, ImGuiPlatformImeData*) {}

#endif

//-----------------------------------------------------------------------------
// [SECTION] METRICS/DEBUGGER WINDOW
//-----------------------------------------------------------------------------
// - RenderViewportThumbnail() [Internal]
// - RenderViewportsThumbnails() [Internal]
// - DebugTextEncoding()
// - MetricsHelpMarker() [Internal]
// - ShowFontAtlas() [Internal]
// - ShowMetricsWindow()
// - DebugNodeColumns() [Internal]
// - DebugNodeDockNode() [Internal]
// - DebugNodeDrawList() [Internal]
// - DebugNodeDrawCmdShowMeshAndBoundingBox() [Internal]
// - DebugNodeFont() [Internal]
// - DebugNodeFontGlyph() [Internal]
// - DebugNodeStorage() [Internal]
// - DebugNodeTabBar() [Internal]
// - DebugNodeViewport() [Internal]
// - DebugNodeWindow() [Internal]
// - DebugNodeWindowSettings() [Internal]
// - DebugNodeWindowsList() [Internal]
// - DebugNodeWindowsListByBeginStackParent() [Internal]
//-----------------------------------------------------------------------------

#ifndef IMGUI_DISABLE_DEBUG_TOOLS

void ImGui::DebugRenderViewportThumbnail(ImDrawList* draw_list, ImGuiViewportP* viewport, const ImRect& bb)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;

    ImVec2 scale = bb.GetSize() / viewport->Size;
    ImVec2 off = bb.Min - viewport->Pos * scale;
    float alpha_mul = (viewport->Flags & ImGuiViewportFlags_IsMinimized) ? 0.30f : 1.00f;
    window->DrawList->AddRectFilled(bb.Min, bb.Max, GetColorU32(ImGuiCol_Border, alpha_mul * 0.40f));
    for (ImGuiWindow* thumb_window : g.Windows)
    {
        if (!thumb_window->WasActive || (thumb_window->Flags & ImGuiWindowFlags_ChildWindow))
            continue;
        if (thumb_window->Viewport != viewport)
            continue;

        ImRect thumb_r = thumb_window->Rect();
        ImRect title_r = thumb_window->TitleBarRect();
        thumb_r = ImRect(ImTrunc(off + thumb_r.Min * scale), ImTrunc(off +  thumb_r.Max * scale));
        title_r = ImRect(ImTrunc(off + title_r.Min * scale), ImTrunc(off +  ImVec2(title_r.Max.x, title_r.Min.y) * scale) + ImVec2(0,5)); // Exaggerate title bar height
        thumb_r.ClipWithFull(bb);
        title_r.ClipWithFull(bb);
        const bool window_is_focused = (g.NavWindow && thumb_window->RootWindowForTitleBarHighlight == g.NavWindow->RootWindowForTitleBarHighlight);
        window->DrawList->AddRectFilled(thumb_r.Min, thumb_r.Max, GetColorU32(ImGuiCol_WindowBg, alpha_mul));
        window->DrawList->AddRectFilled(title_r.Min, title_r.Max, GetColorU32(window_is_focused ? ImGuiCol_TitleBgActive : ImGuiCol_TitleBg, alpha_mul));
        window->DrawList->AddRect(thumb_r.Min, thumb_r.Max, GetColorU32(ImGuiCol_Border, alpha_mul));
        window->DrawList->AddText(g.Font, g.FontSize * 1.0f, title_r.Min, GetColorU32(ImGuiCol_Text, alpha_mul), thumb_window->Name, FindRenderedTextEnd(thumb_window->Name));
    }
    draw_list->AddRect(bb.Min, bb.Max, GetColorU32(ImGuiCol_Border, alpha_mul));
}

static void RenderViewportsThumbnails()
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;

    // We don't display full monitor bounds (we could, but it often looks awkward), instead we display just enough to cover all of our viewports.
    float SCALE = 1.0f / 8.0f;
    ImRect bb_full(FLT_MAX, FLT_MAX, -FLT_MAX, -FLT_MAX);
    for (ImGuiViewportP* viewport : g.Viewports)
        bb_full.Add(viewport->GetMainRect());
    ImVec2 p = window->DC.CursorPos;
    ImVec2 off = p - bb_full.Min * SCALE;
    for (ImGuiViewportP* viewport : g.Viewports)
    {
        ImRect viewport_draw_bb(off + (viewport->Pos) * SCALE, off + (viewport->Pos + viewport->Size) * SCALE);
        ImGui::DebugRenderViewportThumbnail(window->DrawList, viewport, viewport_draw_bb);
    }
    ImGui::Dummy(bb_full.GetSize() * SCALE);
}

static int IMGUI_CDECL ViewportComparerByLastFocusedStampCount(const void* lhs, const void* rhs)
{
    const ImGuiViewportP* a = *(const ImGuiViewportP* const*)lhs;
    const ImGuiViewportP* b = *(const ImGuiViewportP* const*)rhs;
    return b->LastFocusedStampCount - a->LastFocusedStampCount;
}

// Draw an arbitrary US keyboard layout to visualize translated keys
void ImGui::DebugRenderKeyboardPreview(ImDrawList* draw_list)
{
    const ImVec2 key_size = ImVec2(35.0f, 35.0f);
    const float  key_rounding = 3.0f;
    const ImVec2 key_face_size = ImVec2(25.0f, 25.0f);
    const ImVec2 key_face_pos = ImVec2(5.0f, 3.0f);
    const float  key_face_rounding = 2.0f;
    const ImVec2 key_label_pos = ImVec2(7.0f, 4.0f);
    const ImVec2 key_step = ImVec2(key_size.x - 1.0f, key_size.y - 1.0f);
    const float  key_row_offset = 9.0f;

    ImVec2 board_min = GetCursorScreenPos();
    ImVec2 board_max = ImVec2(board_min.x + 3 * key_step.x + 2 * key_row_offset + 10.0f, board_min.y + 3 * key_step.y + 10.0f);
    ImVec2 start_pos = ImVec2(board_min.x + 5.0f - key_step.x, board_min.y);

    struct KeyLayoutData { int Row, Col; const char* Label; ImGuiKey Key; };
    const KeyLayoutData keys_to_display[] =
    {
        { 0, 0, "", ImGuiKey_Tab },      { 0, 1, "Q", ImGuiKey_Q }, { 0, 2, "W", ImGuiKey_W }, { 0, 3, "E", ImGuiKey_E }, { 0, 4, "R", ImGuiKey_R },
        { 1, 0, "", ImGuiKey_CapsLock }, { 1, 1, "A", ImGuiKey_A }, { 1, 2, "S", ImGuiKey_S }, { 1, 3, "D", ImGuiKey_D }, { 1, 4, "F", ImGuiKey_F },
        { 2, 0, "", ImGuiKey_LeftShift },{ 2, 1, "Z", ImGuiKey_Z }, { 2, 2, "X", ImGuiKey_X }, { 2, 3, "C", ImGuiKey_C }, { 2, 4, "V", ImGuiKey_V }
    };

    // Elements rendered manually via ImDrawList API are not clipped automatically.
    // While not strictly necessary, here IsItemVisible() is used to avoid rendering these shapes when they are out of view.
    Dummy(board_max - board_min);
    if (!IsItemVisible())
        return;
    draw_list->PushClipRect(board_min, board_max, true);
    for (int n = 0; n < IM_ARRAYSIZE(keys_to_display); n++)
    {
        const KeyLayoutData* key_data = &keys_to_display[n];
        ImVec2 key_min = ImVec2(start_pos.x + key_data->Col * key_step.x + key_data->Row * key_row_offset, start_pos.y + key_data->Row * key_step.y);
        ImVec2 key_max = key_min + key_size;
        draw_list->AddRectFilled(key_min, key_max, IM_COL32(204, 204, 204, 255), key_rounding);
        draw_list->AddRect(key_min, key_max, IM_COL32(24, 24, 24, 255), key_rounding);
        ImVec2 face_min = ImVec2(key_min.x + key_face_pos.x, key_min.y + key_face_pos.y);
        ImVec2 face_max = ImVec2(face_min.x + key_face_size.x, face_min.y + key_face_size.y);
        draw_list->AddRect(face_min, face_max, IM_COL32(193, 193, 193, 255), key_face_rounding, ImDrawFlags_None, 2.0f);
        draw_list->AddRectFilled(face_min, face_max, IM_COL32(252, 252, 252, 255), key_face_rounding);
        ImVec2 label_min = ImVec2(key_min.x + key_label_pos.x, key_min.y + key_label_pos.y);
        draw_list->AddText(label_min, IM_COL32(64, 64, 64, 255), key_data->Label);
        if (IsKeyDown(key_data->Key))
            draw_list->AddRectFilled(key_min, key_max, IM_COL32(255, 0, 0, 128), key_rounding);
    }
    draw_list->PopClipRect();
}

// Helper tool to diagnose between text encoding issues and font loading issues. Pass your UTF-8 string and verify that there are correct.
void ImGui::DebugTextEncoding(const char* str)
{
    Text("Text: \"%s\"", str);
    if (!BeginTable("##DebugTextEncoding", 4, ImGuiTableFlags_Borders | ImGuiTableFlags_RowBg | ImGuiTableFlags_SizingFixedFit | ImGuiTableFlags_Resizable))
        return;
    TableSetupColumn("Offset");
    TableSetupColumn("UTF-8");
    TableSetupColumn("Glyph");
    TableSetupColumn("Codepoint");
    TableHeadersRow();
    for (const char* p = str; *p != 0; )
    {
        unsigned int c;
        const int c_utf8_len = ImTextCharFromUtf8(&c, p, NULL);
        TableNextColumn();
        Text("%d", (int)(p - str));
        TableNextColumn();
        for (int byte_index = 0; byte_index < c_utf8_len; byte_index++)
        {
            if (byte_index > 0)
                SameLine();
            Text("0x%02X", (int)(unsigned char)p[byte_index]);
        }
        TableNextColumn();
        if (GetFont()->FindGlyphNoFallback((ImWchar)c))
            TextUnformatted(p, p + c_utf8_len);
        else
            TextUnformatted((c == IM_UNICODE_CODEPOINT_INVALID) ? "[invalid]" : "[missing]");
        TableNextColumn();
        Text("U+%04X", (int)c);
        p += c_utf8_len;
    }
    EndTable();
}

// Avoid naming collision with imgui_demo.cpp's HelpMarker() for unity builds.
static void MetricsHelpMarker(const char* desc)
{
    ImGui::TextDisabled("(?)");
    if (ImGui::BeginItemTooltip())
    {
        ImGui::PushTextWrapPos(ImGui::GetFontSize() * 35.0f);
        ImGui::TextUnformatted(desc);
        ImGui::PopTextWrapPos();
        ImGui::EndTooltip();
    }
}

// [DEBUG] List fonts in a font atlas and display its texture
void ImGui::ShowFontAtlas(ImFontAtlas* atlas)
{
    for (ImFont* font : atlas->Fonts)
    {
        PushID(font);
        DebugNodeFont(font);
        PopID();
    }
    if (TreeNode("Font Atlas", "Font Atlas (%dx%d pixels)", atlas->TexWidth, atlas->TexHeight))
    {
        ImGuiContext& g = *GImGui;
        ImGuiMetricsConfig* cfg = &g.DebugMetricsConfig;
        Checkbox("Tint with Text Color", &cfg->ShowAtlasTintedWithTextColor); // Using text color ensure visibility of core atlas data, but will alter custom colored icons
        ImVec4 tint_col = cfg->ShowAtlasTintedWithTextColor ? GetStyleColorVec4(ImGuiCol_Text) : ImVec4(1.0f, 1.0f, 1.0f, 1.0f);
        ImVec4 border_col = GetStyleColorVec4(ImGuiCol_Border);
        Image(atlas->TexID, ImVec2((float)atlas->TexWidth, (float)atlas->TexHeight), ImVec2(0.0f, 0.0f), ImVec2(1.0f, 1.0f), tint_col, border_col);
        TreePop();
    }
}

void ImGui::ShowMetricsWindow(bool* p_open)
{
    ImGuiContext& g = *GImGui;
    ImGuiIO& io = g.IO;
    ImGuiMetricsConfig* cfg = &g.DebugMetricsConfig;
    if (cfg->ShowDebugLog)
        ShowDebugLogWindow(&cfg->ShowDebugLog);
    if (cfg->ShowIDStackTool)
        ShowIDStackToolWindow(&cfg->ShowIDStackTool);

    if (!Begin("Dear ImGui Metrics/Debugger", p_open) || GetCurrentWindow()->BeginCount > 1)
    {
        End();
        return;
    }

    // Basic info
    Text("Dear ImGui %s", GetVersion());
    Text("Application average %.3f ms/frame (%.1f FPS)", 1000.0f / io.Framerate, io.Framerate);
    Text("%d vertices, %d indices (%d triangles)", io.MetricsRenderVertices, io.MetricsRenderIndices, io.MetricsRenderIndices / 3);
    Text("%d visible windows, %d current allocations", io.MetricsRenderWindows, g.DebugAllocInfo.TotalAllocCount - g.DebugAllocInfo.TotalFreeCount);
    //SameLine(); if (SmallButton("GC")) { g.GcCompactAll = true; }

    Separator();

    // Debugging enums
    enum { WRT_OuterRect, WRT_OuterRectClipped, WRT_InnerRect, WRT_InnerClipRect, WRT_WorkRect, WRT_Content, WRT_ContentIdeal, WRT_ContentRegionRect, WRT_Count }; // Windows Rect Type
    const char* wrt_rects_names[WRT_Count] = { "OuterRect", "OuterRectClipped", "InnerRect", "InnerClipRect", "WorkRect", "Content", "ContentIdeal", "ContentRegionRect" };
    enum { TRT_OuterRect, TRT_InnerRect, TRT_WorkRect, TRT_HostClipRect, TRT_InnerClipRect, TRT_BackgroundClipRect, TRT_ColumnsRect, TRT_ColumnsWorkRect, TRT_ColumnsClipRect, TRT_ColumnsContentHeadersUsed, TRT_ColumnsContentHeadersIdeal, TRT_ColumnsContentFrozen, TRT_ColumnsContentUnfrozen, TRT_Count }; // Tables Rect Type
    const char* trt_rects_names[TRT_Count] = { "OuterRect", "InnerRect", "WorkRect", "HostClipRect", "InnerClipRect", "BackgroundClipRect", "ColumnsRect", "ColumnsWorkRect", "ColumnsClipRect", "ColumnsContentHeadersUsed", "ColumnsContentHeadersIdeal", "ColumnsContentFrozen", "ColumnsContentUnfrozen" };
    if (cfg->ShowWindowsRectsType < 0)
        cfg->ShowWindowsRectsType = WRT_WorkRect;
    if (cfg->ShowTablesRectsType < 0)
        cfg->ShowTablesRectsType = TRT_WorkRect;

    struct Funcs
    {
        static ImRect GetTableRect(ImGuiTable* table, int rect_type, int n)
        {
            ImGuiTableInstanceData* table_instance = TableGetInstanceData(table, table->InstanceCurrent); // Always using last submitted instance
            if (rect_type == TRT_OuterRect)                     { return table->OuterRect; }
            else if (rect_type == TRT_InnerRect)                { return table->InnerRect; }
            else if (rect_type == TRT_WorkRect)                 { return table->WorkRect; }
            else if (rect_type == TRT_HostClipRect)             { return table->HostClipRect; }
            else if (rect_type == TRT_InnerClipRect)            { return table->InnerClipRect; }
            else if (rect_type == TRT_BackgroundClipRect)       { return table->BgClipRect; }
            else if (rect_type == TRT_ColumnsRect)              { ImGuiTableColumn* c = &table->Columns[n]; return ImRect(c->MinX, table->InnerClipRect.Min.y, c->MaxX, table->InnerClipRect.Min.y + table_instance->LastOuterHeight); }
            else if (rect_type == TRT_ColumnsWorkRect)          { ImGuiTableColumn* c = &table->Columns[n]; return ImRect(c->WorkMinX, table->WorkRect.Min.y, c->WorkMaxX, table->WorkRect.Max.y); }
            else if (rect_type == TRT_ColumnsClipRect)          { ImGuiTableColumn* c = &table->Columns[n]; return c->ClipRect; }
            else if (rect_type == TRT_ColumnsContentHeadersUsed){ ImGuiTableColumn* c = &table->Columns[n]; return ImRect(c->WorkMinX, table->InnerClipRect.Min.y, c->ContentMaxXHeadersUsed, table->InnerClipRect.Min.y + table_instance->LastTopHeadersRowHeight); } // Note: y1/y2 not always accurate
            else if (rect_type == TRT_ColumnsContentHeadersIdeal){ImGuiTableColumn* c = &table->Columns[n]; return ImRect(c->WorkMinX, table->InnerClipRect.Min.y, c->ContentMaxXHeadersIdeal, table->InnerClipRect.Min.y + table_instance->LastTopHeadersRowHeight); }
            else if (rect_type == TRT_ColumnsContentFrozen)     { ImGuiTableColumn* c = &table->Columns[n]; return ImRect(c->WorkMinX, table->InnerClipRect.Min.y, c->ContentMaxXFrozen, table->InnerClipRect.Min.y + table_instance->LastFrozenHeight); }
            else if (rect_type == TRT_ColumnsContentUnfrozen)   { ImGuiTableColumn* c = &table->Columns[n]; return ImRect(c->WorkMinX, table->InnerClipRect.Min.y + table_instance->LastFrozenHeight, c->ContentMaxXUnfrozen, table->InnerClipRect.Max.y); }
            IM_ASSERT(0);
            return ImRect();
        }

        static ImRect GetWindowRect(ImGuiWindow* window, int rect_type)
        {
            if (rect_type == WRT_OuterRect)                 { return window->Rect(); }
            else if (rect_type == WRT_OuterRectClipped)     { return window->OuterRectClipped; }
            else if (rect_type == WRT_InnerRect)            { return window->InnerRect; }
            else if (rect_type == WRT_InnerClipRect)        { return window->InnerClipRect; }
            else if (rect_type == WRT_WorkRect)             { return window->WorkRect; }
            else if (rect_type == WRT_Content)              { ImVec2 min = window->InnerRect.Min - window->Scroll + window->WindowPadding; return ImRect(min, min + window->ContentSize); }
            else if (rect_type == WRT_ContentIdeal)         { ImVec2 min = window->InnerRect.Min - window->Scroll + window->WindowPadding; return ImRect(min, min + window->ContentSizeIdeal); }
            else if (rect_type == WRT_ContentRegionRect)    { return window->ContentRegionRect; }
            IM_ASSERT(0);
            return ImRect();
        }
    };

    // Tools
    if (TreeNode("Tools"))
    {
        bool show_encoding_viewer = TreeNode("UTF-8 Encoding viewer");
        SameLine();
        MetricsHelpMarker("You can also call ImGui::DebugTextEncoding() from your code with a given string to test that your UTF-8 encoding settings are correct.");
        if (show_encoding_viewer)
        {
            static char buf[100] = "";
            SetNextItemWidth(-FLT_MIN);
            InputText("##Text", buf, IM_ARRAYSIZE(buf));
            if (buf[0] != 0)
                DebugTextEncoding(buf);
            TreePop();
        }

        // The Item Picker tool is super useful to visually select an item and break into the call-stack of where it was submitted.
        if (Checkbox("Show Item Picker", &g.DebugItemPickerActive) && g.DebugItemPickerActive)
            DebugStartItemPicker();
        SameLine();
        MetricsHelpMarker("Will call the IM_DEBUG_BREAK() macro to break in debugger.\nWarning: If you don't have a debugger attached, this will probably crash.");

        Checkbox("Show Debug Log", &cfg->ShowDebugLog);
        SameLine();
        MetricsHelpMarker("You can also call ImGui::ShowDebugLogWindow() from your code.");

        Checkbox("Show ID Stack Tool", &cfg->ShowIDStackTool);
        SameLine();
        MetricsHelpMarker("You can also call ImGui::ShowIDStackToolWindow() from your code.");

        Checkbox("Show windows begin order", &cfg->ShowWindowsBeginOrder);
        Checkbox("Show windows rectangles", &cfg->ShowWindowsRects);
        SameLine();
        SetNextItemWidth(GetFontSize() * 12);
        cfg->ShowWindowsRects |= Combo("##show_windows_rect_type", &cfg->ShowWindowsRectsType, wrt_rects_names, WRT_Count, WRT_Count);
        if (cfg->ShowWindowsRects && g.NavWindow != NULL)
        {
            BulletText("'%s':", g.NavWindow->Name);
            Indent();
            for (int rect_n = 0; rect_n < WRT_Count; rect_n++)
            {
                ImRect r = Funcs::GetWindowRect(g.NavWindow, rect_n);
                Text("(%6.1f,%6.1f) (%6.1f,%6.1f) Size (%6.1f,%6.1f) %s", r.Min.x, r.Min.y, r.Max.x, r.Max.y, r.GetWidth(), r.GetHeight(), wrt_rects_names[rect_n]);
            }
            Unindent();
        }

        Checkbox("Show tables rectangles", &cfg->ShowTablesRects);
        SameLine();
        SetNextItemWidth(GetFontSize() * 12);
        cfg->ShowTablesRects |= Combo("##show_table_rects_type", &cfg->ShowTablesRectsType, trt_rects_names, TRT_Count, TRT_Count);
        if (cfg->ShowTablesRects && g.NavWindow != NULL)
        {
            for (int table_n = 0; table_n < g.Tables.GetMapSize(); table_n++)
            {
                ImGuiTable* table = g.Tables.TryGetMapData(table_n);
                if (table == NULL || table->LastFrameActive < g.FrameCount - 1 || (table->OuterWindow != g.NavWindow && table->InnerWindow != g.NavWindow))
                    continue;

                BulletText("Table 0x%08X (%d columns, in '%s')", table->ID, table->ColumnsCount, table->OuterWindow->Name);
                if (IsItemHovered())
                    GetForegroundDrawList()->AddRect(table->OuterRect.Min - ImVec2(1, 1), table->OuterRect.Max + ImVec2(1, 1), IM_COL32(255, 255, 0, 255), 0.0f, 0, 2.0f);
                Indent();
                char buf[128];
                for (int rect_n = 0; rect_n < TRT_Count; rect_n++)
                {
                    if (rect_n >= TRT_ColumnsRect)
                    {
                        if (rect_n != TRT_ColumnsRect && rect_n != TRT_ColumnsClipRect)
                            continue;
                        for (int column_n = 0; column_n < table->ColumnsCount; column_n++)
                        {
                            ImRect r = Funcs::GetTableRect(table, rect_n, column_n);
                            ImFormatString(buf, IM_ARRAYSIZE(buf), "(%6.1f,%6.1f) (%6.1f,%6.1f) Size (%6.1f,%6.1f) Col %d %s", r.Min.x, r.Min.y, r.Max.x, r.Max.y, r.GetWidth(), r.GetHeight(), column_n, trt_rects_names[rect_n]);
                            Selectable(buf);
                            if (IsItemHovered())
                                GetForegroundDrawList()->AddRect(r.Min - ImVec2(1, 1), r.Max + ImVec2(1, 1), IM_COL32(255, 255, 0, 255), 0.0f, 0, 2.0f);
                        }
                    }
                    else
                    {
                        ImRect r = Funcs::GetTableRect(table, rect_n, -1);
                        ImFormatString(buf, IM_ARRAYSIZE(buf), "(%6.1f,%6.1f) (%6.1f,%6.1f) Size (%6.1f,%6.1f) %s", r.Min.x, r.Min.y, r.Max.x, r.Max.y, r.GetWidth(), r.GetHeight(), trt_rects_names[rect_n]);
                        Selectable(buf);
                        if (IsItemHovered())
                            GetForegroundDrawList()->AddRect(r.Min - ImVec2(1, 1), r.Max + ImVec2(1, 1), IM_COL32(255, 255, 0, 255), 0.0f, 0, 2.0f);
                    }
                }
                Unindent();
            }
        }
        Checkbox("Show groups rectangles", &g.DebugShowGroupRects); // Storing in context as this is used by group code and prefers to be in hot-data

        Checkbox("Debug Begin/BeginChild return value", &io.ConfigDebugBeginReturnValueLoop);
        SameLine();
        MetricsHelpMarker("Some calls to Begin()/BeginChild() will return false.\n\nWill cycle through window depths then repeat. Windows should be flickering while running.");

        TreePop();
    }

    // Windows
    if (TreeNode("Windows", "Windows (%d)", g.Windows.Size))
    {
        //SetNextItemOpen(true, ImGuiCond_Once);
        DebugNodeWindowsList(&g.Windows, "By display order");
        DebugNodeWindowsList(&g.WindowsFocusOrder, "By focus order (root windows)");
        if (TreeNode("By submission order (begin stack)"))
        {
            // Here we display windows in their submitted order/hierarchy, however note that the Begin stack doesn't constitute a Parent<>Child relationship!
            ImVector<ImGuiWindow*>& temp_buffer = g.WindowsTempSortBuffer;
            temp_buffer.resize(0);
            for (ImGuiWindow* window : g.Windows)
                if (window->LastFrameActive + 1 >= g.FrameCount)
                    temp_buffer.push_back(window);
            struct Func { static int IMGUI_CDECL WindowComparerByBeginOrder(const void* lhs, const void* rhs) { return ((int)(*(const ImGuiWindow* const *)lhs)->BeginOrderWithinContext - (*(const ImGuiWindow* const*)rhs)->BeginOrderWithinContext); } };
            ImQsort(temp_buffer.Data, (size_t)temp_buffer.Size, sizeof(ImGuiWindow*), Func::WindowComparerByBeginOrder);
            DebugNodeWindowsListByBeginStackParent(temp_buffer.Data, temp_buffer.Size, NULL);
            TreePop();
        }

        TreePop();
    }

    // DrawLists
    int drawlist_count = 0;
    for (ImGuiViewportP* viewport : g.Viewports)
        drawlist_count += viewport->DrawDataP.CmdLists.Size;
    if (TreeNode("DrawLists", "DrawLists (%d)", drawlist_count))
    {
        Checkbox("Show ImDrawCmd mesh when hovering", &cfg->ShowDrawCmdMesh);
        Checkbox("Show ImDrawCmd bounding boxes when hovering", &cfg->ShowDrawCmdBoundingBoxes);
        for (ImGuiViewportP* viewport : g.Viewports)
        {
            bool viewport_has_drawlist = false;
            for (ImDrawList* draw_list : viewport->DrawDataP.CmdLists)
            {
                if (!viewport_has_drawlist)
                    Text("Active DrawLists in Viewport #%d, ID: 0x%08X", viewport->Idx, viewport->ID);
                viewport_has_drawlist = true;
                DebugNodeDrawList(NULL, viewport, draw_list, "DrawList");
            }
        }
        TreePop();
    }

    // Viewports
    if (TreeNode("Viewports", "Viewports (%d)", g.Viewports.Size))
    {
        Indent(GetTreeNodeToLabelSpacing());
        RenderViewportsThumbnails();
        Unindent(GetTreeNodeToLabelSpacing());

        bool open = TreeNode("Monitors", "Monitors (%d)", g.PlatformIO.Monitors.Size);
        SameLine();
        MetricsHelpMarker("Dear ImGui uses monitor data:\n- to query DPI settings on a per monitor basis\n- to position popup/tooltips so they don't straddle monitors.");
        if (open)
        {
            for (int i = 0; i < g.PlatformIO.Monitors.Size; i++)
            {
                const ImGuiPlatformMonitor& mon = g.PlatformIO.Monitors[i];
                BulletText("Monitor #%d: DPI %.0f%%\n MainMin (%.0f,%.0f), MainMax (%.0f,%.0f), MainSize (%.0f,%.0f)\n WorkMin (%.0f,%.0f), WorkMax (%.0f,%.0f), WorkSize (%.0f,%.0f)",
                    i, mon.DpiScale * 100.0f,
                    mon.MainPos.x, mon.MainPos.y, mon.MainPos.x + mon.MainSize.x, mon.MainPos.y + mon.MainSize.y, mon.MainSize.x, mon.MainSize.y,
                    mon.WorkPos.x, mon.WorkPos.y, mon.WorkPos.x + mon.WorkSize.x, mon.WorkPos.y + mon.WorkSize.y, mon.WorkSize.x, mon.WorkSize.y);
            }
            TreePop();
        }

        BulletText("MouseViewport: 0x%08X (UserHovered 0x%08X, LastHovered 0x%08X)", g.MouseViewport ? g.MouseViewport->ID : 0, g.IO.MouseHoveredViewport, g.MouseLastHoveredViewport ? g.MouseLastHoveredViewport->ID : 0);
        if (TreeNode("Inferred Z order (front-to-back)"))
        {
            static ImVector<ImGuiViewportP*> viewports;
            viewports.resize(g.Viewports.Size);
            memcpy(viewports.Data, g.Viewports.Data, g.Viewports.size_in_bytes());
            if (viewports.Size > 1)
                ImQsort(viewports.Data, viewports.Size, sizeof(ImGuiViewport*), ViewportComparerByLastFocusedStampCount);
            for (ImGuiViewportP* viewport : viewports)
                BulletText("Viewport #%d, ID: 0x%08X, LastFocused = %08d, PlatformFocused = %s, Window: \"%s\"",
                    viewport->Idx, viewport->ID, viewport->LastFocusedStampCount,
                    (g.PlatformIO.Platform_GetWindowFocus && viewport->PlatformWindowCreated) ? (g.PlatformIO.Platform_GetWindowFocus(viewport) ? "1" : "0") : "N/A",
                    viewport->Window ? viewport->Window->Name : "N/A");
            TreePop();
        }
        for (ImGuiViewportP* viewport : g.Viewports)
            DebugNodeViewport(viewport);
        TreePop();
    }

    // Details for Popups
    if (TreeNode("Popups", "Popups (%d)", g.OpenPopupStack.Size))
    {
        for (const ImGuiPopupData& popup_data : g.OpenPopupStack)
        {
            // As it's difficult to interact with tree nodes while popups are open, we display everything inline.
            ImGuiWindow* window = popup_data.Window;
            BulletText("PopupID: %08x, Window: '%s' (%s%s), BackupNavWindow '%s', ParentWindow '%s'",
                popup_data.PopupId, window ? window->Name : "NULL", window && (window->Flags & ImGuiWindowFlags_ChildWindow) ? "Child;" : "", window && (window->Flags & ImGuiWindowFlags_ChildMenu) ? "Menu;" : "",
                popup_data.BackupNavWindow ? popup_data.BackupNavWindow->Name : "NULL", window && window->ParentWindow ? window->ParentWindow->Name : "NULL");
        }
        TreePop();
    }

    // Details for TabBars
    if (TreeNode("TabBars", "Tab Bars (%d)", g.TabBars.GetAliveCount()))
    {
        for (int n = 0; n < g.TabBars.GetMapSize(); n++)
            if (ImGuiTabBar* tab_bar = g.TabBars.TryGetMapData(n))
            {
                PushID(tab_bar);
                DebugNodeTabBar(tab_bar, "TabBar");
                PopID();
            }
        TreePop();
    }

    // Details for Tables
    if (TreeNode("Tables", "Tables (%d)", g.Tables.GetAliveCount()))
    {
        for (int n = 0; n < g.Tables.GetMapSize(); n++)
            if (ImGuiTable* table = g.Tables.TryGetMapData(n))
                DebugNodeTable(table);
        TreePop();
    }

    // Details for Fonts
    ImFontAtlas* atlas = g.IO.Fonts;
    if (TreeNode("Fonts", "Fonts (%d)", atlas->Fonts.Size))
    {
        ShowFontAtlas(atlas);
        TreePop();
    }

    // Details for InputText
    if (TreeNode("InputText"))
    {
        DebugNodeInputTextState(&g.InputTextState);
        TreePop();
    }

    // Details for TypingSelect
    if (TreeNode("TypingSelect", "TypingSelect (%d)", g.TypingSelectState.SearchBuffer[0] != 0 ? 1 : 0))
    {
        DebugNodeTypingSelectState(&g.TypingSelectState);
        TreePop();
    }

    // Details for Docking
#ifdef IMGUI_HAS_DOCK
    if (TreeNode("Docking"))
    {
        static bool root_nodes_only = true;
        ImGuiDockContext* dc = &g.DockContext;
        Checkbox("List root nodes", &root_nodes_only);
        Checkbox("Ctrl shows window dock info", &cfg->ShowDockingNodes);
        if (SmallButton("Clear nodes")) { DockContextClearNodes(&g, 0, true); }
        SameLine();
        if (SmallButton("Rebuild all")) { dc->WantFullRebuild = true; }
        for (int n = 0; n < dc->Nodes.Data.Size; n++)
            if (ImGuiDockNode* node = (ImGuiDockNode*)dc->Nodes.Data[n].val_p)
                if (!root_nodes_only || node->IsRootNode())
                    DebugNodeDockNode(node, "Node");
        TreePop();
    }
#endif // #ifdef IMGUI_HAS_DOCK

    // Settings
    if (TreeNode("Settings"))
    {
        if (SmallButton("Clear"))
            ClearIniSettings();
        SameLine();
        if (SmallButton("Save to memory"))
            SaveIniSettingsToMemory();
        SameLine();
        if (SmallButton("Save to disk"))
            SaveIniSettingsToDisk(g.IO.IniFilename);
        SameLine();
        if (g.IO.IniFilename)
            Text("\"%s\"", g.IO.IniFilename);
        else
            TextUnformatted("<NULL>");
        Checkbox("io.ConfigDebugIniSettings", &io.ConfigDebugIniSettings);
        Text("SettingsDirtyTimer %.2f", g.SettingsDirtyTimer);
        if (TreeNode("SettingsHandlers", "Settings handlers: (%d)", g.SettingsHandlers.Size))
        {
            for (ImGuiSettingsHandler& handler : g.SettingsHandlers)
                BulletText("\"%s\"", handler.TypeName);
            TreePop();
        }
        if (TreeNode("SettingsWindows", "Settings packed data: Windows: %d bytes", g.SettingsWindows.size()))
        {
            for (ImGuiWindowSettings* settings = g.SettingsWindows.begin(); settings != NULL; settings = g.SettingsWindows.next_chunk(settings))
                DebugNodeWindowSettings(settings);
            TreePop();
        }

        if (TreeNode("SettingsTables", "Settings packed data: Tables: %d bytes", g.SettingsTables.size()))
        {
            for (ImGuiTableSettings* settings = g.SettingsTables.begin(); settings != NULL; settings = g.SettingsTables.next_chunk(settings))
                DebugNodeTableSettings(settings);
            TreePop();
        }

#ifdef IMGUI_HAS_DOCK
        if (TreeNode("SettingsDocking", "Settings packed data: Docking"))
        {
            ImGuiDockContext* dc = &g.DockContext;
            Text("In SettingsWindows:");
            for (ImGuiWindowSettings* settings = g.SettingsWindows.begin(); settings != NULL; settings = g.SettingsWindows.next_chunk(settings))
                if (settings->DockId != 0)
                    BulletText("Window '%s' -> DockId %08X DockOrder=%d", settings->GetName(), settings->DockId, settings->DockOrder);
            Text("In SettingsNodes:");
            for (int n = 0; n < dc->NodesSettings.Size; n++)
            {
                ImGuiDockNodeSettings* settings = &dc->NodesSettings[n];
                const char* selected_tab_name = NULL;
                if (settings->SelectedTabId)
                {
                    if (ImGuiWindow* window = FindWindowByID(settings->SelectedTabId))
                        selected_tab_name = window->Name;
                    else if (ImGuiWindowSettings* window_settings = FindWindowSettingsByID(settings->SelectedTabId))
                        selected_tab_name = window_settings->GetName();
                }
                BulletText("Node %08X, Parent %08X, SelectedTab %08X ('%s')", settings->ID, settings->ParentNodeId, settings->SelectedTabId, selected_tab_name ? selected_tab_name : settings->SelectedTabId ? "N/A" : "");
            }
            TreePop();
        }
#endif // #ifdef IMGUI_HAS_DOCK

        if (TreeNode("SettingsIniData", "Settings unpacked data (.ini): %d bytes", g.SettingsIniData.size()))
        {
            InputTextMultiline("##Ini", (char*)(void*)g.SettingsIniData.c_str(), g.SettingsIniData.Buf.Size, ImVec2(-FLT_MIN, GetTextLineHeight() * 20), ImGuiInputTextFlags_ReadOnly);
            TreePop();
        }
        TreePop();
    }

    // Settings
    if (TreeNode("Memory allocations"))
    {
        ImGuiDebugAllocInfo* info = &g.DebugAllocInfo;
        Text("%d current allocations", info->TotalAllocCount - info->TotalFreeCount);
        Text("Recent frames with allocations:");
        int buf_size = IM_ARRAYSIZE(info->LastEntriesBuf);
        for (int n = buf_size - 1; n >= 0; n--)
        {
            ImGuiDebugAllocEntry* entry = &info->LastEntriesBuf[(info->LastEntriesIdx - n + buf_size) % buf_size];
            BulletText("Frame %06d: %+3d ( %2d malloc, %2d free )%s", entry->FrameCount, entry->AllocCount - entry->FreeCount, entry->AllocCount, entry->FreeCount, (n == 0) ? " (most recent)" : "");
        }
        TreePop();
    }

    if (TreeNode("Inputs"))
    {
        Text("KEYBOARD/GAMEPAD/MOUSE KEYS");
        {
            // We iterate both legacy native range and named ImGuiKey ranges, which is a little odd but this allows displaying the data for old/new backends.
            // User code should never have to go through such hoops! You can generally iterate between ImGuiKey_NamedKey_BEGIN and ImGuiKey_NamedKey_END.
            Indent();
#ifdef IMGUI_DISABLE_OBSOLETE_KEYIO
            struct funcs { static bool IsLegacyNativeDupe(ImGuiKey) { return false; } };
#else
            struct funcs { static bool IsLegacyNativeDupe(ImGuiKey key) { return key < 512 && GetIO().KeyMap[key] != -1; } }; // Hide Native<>ImGuiKey duplicates when both exists in the array
            //Text("Legacy raw:");      for (ImGuiKey key = ImGuiKey_KeysData_OFFSET; key < ImGuiKey_COUNT; key++) { if (io.KeysDown[key]) { SameLine(); Text("\"%s\" %d", GetKeyName(key), key); } }
#endif
            Text("Keys down:");         for (ImGuiKey key = ImGuiKey_KeysData_OFFSET; key < ImGuiKey_COUNT; key = (ImGuiKey)(key + 1)) { if (funcs::IsLegacyNativeDupe(key) || !IsKeyDown(key)) continue;     SameLine(); Text(IsNamedKey(key) ? "\"%s\"" : "\"%s\" %d", GetKeyName(key), key); SameLine(); Text("(%.02f)", GetKeyData(key)->DownDuration); }
            Text("Keys pressed:");      for (ImGuiKey key = ImGuiKey_KeysData_OFFSET; key < ImGuiKey_COUNT; key = (ImGuiKey)(key + 1)) { if (funcs::IsLegacyNativeDupe(key) || !IsKeyPressed(key)) continue;  SameLine(); Text(IsNamedKey(key) ? "\"%s\"" : "\"%s\" %d", GetKeyName(key), key); }
            Text("Keys released:");     for (ImGuiKey key = ImGuiKey_KeysData_OFFSET; key < ImGuiKey_COUNT; key = (ImGuiKey)(key + 1)) { if (funcs::IsLegacyNativeDupe(key) || !IsKeyReleased(key)) continue; SameLine(); Text(IsNamedKey(key) ? "\"%s\"" : "\"%s\" %d", GetKeyName(key), key); }
            Text("Keys mods: %s%s%s%s", io.KeyCtrl ? "CTRL " : "", io.KeyShift ? "SHIFT " : "", io.KeyAlt ? "ALT " : "", io.KeySuper ? "SUPER " : "");
            Text("Chars queue:");       for (int i = 0; i < io.InputQueueCharacters.Size; i++) { ImWchar c = io.InputQueueCharacters[i]; SameLine(); Text("\'%c\' (0x%04X)", (c > ' ' && c <= 255) ? (char)c : '?', c); } // FIXME: We should convert 'c' to UTF-8 here but the functions are not public.
            DebugRenderKeyboardPreview(GetWindowDrawList());
            Unindent();
        }

        Text("MOUSE STATE");
        {
            Indent();
            if (IsMousePosValid())
                Text("Mouse pos: (%g, %g)", io.MousePos.x, io.MousePos.y);
            else
                Text("Mouse pos: <INVALID>");
            Text("Mouse delta: (%g, %g)", io.MouseDelta.x, io.MouseDelta.y);
            int count = IM_ARRAYSIZE(io.MouseDown);
            Text("Mouse down:");     for (int i = 0; i < count; i++) if (IsMouseDown(i)) { SameLine(); Text("b%d (%.02f secs)", i, io.MouseDownDuration[i]); }
            Text("Mouse clicked:");  for (int i = 0; i < count; i++) if (IsMouseClicked(i)) { SameLine(); Text("b%d (%d)", i, io.MouseClickedCount[i]); }
            Text("Mouse released:"); for (int i = 0; i < count; i++) if (IsMouseReleased(i)) { SameLine(); Text("b%d", i); }
            Text("Mouse wheel: %.1f", io.MouseWheel);
            Text("MouseStationaryTimer: %.2f", g.MouseStationaryTimer);
            Text("Mouse source: %s", GetMouseSourceName(io.MouseSource));
            Text("Pen Pressure: %.1f", io.PenPressure); // Note: currently unused
            Unindent();
        }

        Text("MOUSE WHEELING");
        {
            Indent();
            Text("WheelingWindow: '%s'", g.WheelingWindow ? g.WheelingWindow->Name : "NULL");
            Text("WheelingWindowReleaseTimer: %.2f", g.WheelingWindowReleaseTimer);
            Text("WheelingAxisAvg[] = { %.3f, %.3f }, Main Axis: %s", g.WheelingAxisAvg.x, g.WheelingAxisAvg.y, (g.WheelingAxisAvg.x > g.WheelingAxisAvg.y) ? "X" : (g.WheelingAxisAvg.x < g.WheelingAxisAvg.y) ? "Y" : "<none>");
            Unindent();
        }

        Text("KEY OWNERS");
        {
            Indent();
            if (BeginChild("##owners", ImVec2(-FLT_MIN, GetTextLineHeightWithSpacing() * 6), ImGuiChildFlags_FrameStyle | ImGuiChildFlags_ResizeY, ImGuiWindowFlags_NoSavedSettings))
                for (ImGuiKey key = ImGuiKey_NamedKey_BEGIN; key < ImGuiKey_NamedKey_END; key = (ImGuiKey)(key + 1))
                {
                    ImGuiKeyOwnerData* owner_data = GetKeyOwnerData(&g, key);
                    if (owner_data->OwnerCurr == ImGuiKeyOwner_None)
                        continue;
                    Text("%s: 0x%08X%s", GetKeyName(key), owner_data->OwnerCurr,
                        owner_data->LockUntilRelease ? " LockUntilRelease" : owner_data->LockThisFrame ? " LockThisFrame" : "");
                    DebugLocateItemOnHover(owner_data->OwnerCurr);
                }
            EndChild();
            Unindent();
        }
        Text("SHORTCUT ROUTING");
        {
            Indent();
            if (BeginChild("##routes", ImVec2(-FLT_MIN, GetTextLineHeightWithSpacing() * 6), ImGuiChildFlags_FrameStyle | ImGuiChildFlags_ResizeY, ImGuiWindowFlags_NoSavedSettings))
                for (ImGuiKey key = ImGuiKey_NamedKey_BEGIN; key < ImGuiKey_NamedKey_END; key = (ImGuiKey)(key + 1))
                {
                    ImGuiKeyRoutingTable* rt = &g.KeysRoutingTable;
                    for (ImGuiKeyRoutingIndex idx = rt->Index[key - ImGuiKey_NamedKey_BEGIN]; idx != -1; )
                    {
                        char key_chord_name[64];
                        ImGuiKeyRoutingData* routing_data = &rt->Entries[idx];
                        GetKeyChordName(key | routing_data->Mods, key_chord_name, IM_ARRAYSIZE(key_chord_name));
                        Text("%s: 0x%08X", key_chord_name, routing_data->RoutingCurr);
                        DebugLocateItemOnHover(routing_data->RoutingCurr);
                        idx = routing_data->NextEntryIndex;
                    }
                }
            EndChild();
            Text("(ActiveIdUsing: AllKeyboardKeys: %d, NavDirMask: 0x%X)", g.ActiveIdUsingAllKeyboardKeys, g.ActiveIdUsingNavDirMask);
            Unindent();
        }
        TreePop();
    }

    if (TreeNode("Internal state"))
    {
        Text("WINDOWING");
        Indent();
        Text("HoveredWindow: '%s'", g.HoveredWindow ? g.HoveredWindow->Name : "NULL");
        Text("HoveredWindow->Root: '%s'", g.HoveredWindow ? g.HoveredWindow->RootWindowDockTree->Name : "NULL");
        Text("HoveredWindowUnderMovingWindow: '%s'", g.HoveredWindowUnderMovingWindow ? g.HoveredWindowUnderMovingWindow->Name : "NULL");
        Text("HoveredDockNode: 0x%08X", g.DebugHoveredDockNode ? g.DebugHoveredDockNode->ID : 0);
        Text("MovingWindow: '%s'", g.MovingWindow ? g.MovingWindow->Name : "NULL");
        Text("MouseViewport: 0x%08X (UserHovered 0x%08X, LastHovered 0x%08X)", g.MouseViewport->ID, g.IO.MouseHoveredViewport, g.MouseLastHoveredViewport ? g.MouseLastHoveredViewport->ID : 0);
        Unindent();

        Text("ITEMS");
        Indent();
        Text("ActiveId: 0x%08X/0x%08X (%.2f sec), AllowOverlap: %d, Source: %s", g.ActiveId, g.ActiveIdPreviousFrame, g.ActiveIdTimer, g.ActiveIdAllowOverlap, GetInputSourceName(g.ActiveIdSource));
        DebugLocateItemOnHover(g.ActiveId);
        Text("ActiveIdWindow: '%s'", g.ActiveIdWindow ? g.ActiveIdWindow->Name : "NULL");
        Text("ActiveIdUsing: AllKeyboardKeys: %d, NavDirMask: %X", g.ActiveIdUsingAllKeyboardKeys, g.ActiveIdUsingNavDirMask);
        Text("HoveredId: 0x%08X (%.2f sec), AllowOverlap: %d", g.HoveredIdPreviousFrame, g.HoveredIdTimer, g.HoveredIdAllowOverlap); // Not displaying g.HoveredId as it is update mid-frame
        Text("HoverItemDelayId: 0x%08X, Timer: %.2f, ClearTimer: %.2f", g.HoverItemDelayId, g.HoverItemDelayTimer, g.HoverItemDelayClearTimer);
        Text("DragDrop: %d, SourceId = 0x%08X, Payload \"%s\" (%d bytes)", g.DragDropActive, g.DragDropPayload.SourceId, g.DragDropPayload.DataType, g.DragDropPayload.DataSize);
        DebugLocateItemOnHover(g.DragDropPayload.SourceId);
        Unindent();

        Text("NAV,FOCUS");
        Indent();
        Text("NavWindow: '%s'", g.NavWindow ? g.NavWindow->Name : "NULL");
        Text("NavId: 0x%08X, NavLayer: %d", g.NavId, g.NavLayer);
        DebugLocateItemOnHover(g.NavId);
        Text("NavInputSource: %s", GetInputSourceName(g.NavInputSource));
        Text("NavLastValidSelectionUserData = %" IM_PRId64 " (0x%" IM_PRIX64 ")", g.NavLastValidSelectionUserData, g.NavLastValidSelectionUserData);
        Text("NavActive: %d, NavVisible: %d", g.IO.NavActive, g.IO.NavVisible);
        Text("NavActivateId/DownId/PressedId: %08X/%08X/%08X", g.NavActivateId, g.NavActivateDownId, g.NavActivatePressedId);
        Text("NavActivateFlags: %04X", g.NavActivateFlags);
        Text("NavDisableHighlight: %d, NavDisableMouseHover: %d", g.NavDisableHighlight, g.NavDisableMouseHover);
        Text("NavFocusScopeId = 0x%08X", g.NavFocusScopeId);
        Text("NavWindowingTarget: '%s'", g.NavWindowingTarget ? g.NavWindowingTarget->Name : "NULL");
        Unindent();

        TreePop();
    }

    // Overlay: Display windows Rectangles and Begin Order
    if (cfg->ShowWindowsRects || cfg->ShowWindowsBeginOrder)
    {
        for (ImGuiWindow* window : g.Windows)
        {
            if (!window->WasActive)
                continue;
            ImDrawList* draw_list = GetForegroundDrawList(window);
            if (cfg->ShowWindowsRects)
            {
                ImRect r = Funcs::GetWindowRect(window, cfg->ShowWindowsRectsType);
                draw_list->AddRect(r.Min, r.Max, IM_COL32(255, 0, 128, 255));
            }
            if (cfg->ShowWindowsBeginOrder && !(window->Flags & ImGuiWindowFlags_ChildWindow))
            {
                char buf[32];
                ImFormatString(buf, IM_ARRAYSIZE(buf), "%d", window->BeginOrderWithinContext);
                float font_size = GetFontSize();
                draw_list->AddRectFilled(window->Pos, window->Pos + ImVec2(font_size, font_size), IM_COL32(200, 100, 100, 255));
                draw_list->AddText(window->Pos, IM_COL32(255, 255, 255, 255), buf);
            }
        }
    }

    // Overlay: Display Tables Rectangles
    if (cfg->ShowTablesRects)
    {
        for (int table_n = 0; table_n < g.Tables.GetMapSize(); table_n++)
        {
            ImGuiTable* table = g.Tables.TryGetMapData(table_n);
            if (table == NULL || table->LastFrameActive < g.FrameCount - 1)
                continue;
            ImDrawList* draw_list = GetForegroundDrawList(table->OuterWindow);
            if (cfg->ShowTablesRectsType >= TRT_ColumnsRect)
            {
                for (int column_n = 0; column_n < table->ColumnsCount; column_n++)
                {
                    ImRect r = Funcs::GetTableRect(table, cfg->ShowTablesRectsType, column_n);
                    ImU32 col = (table->HoveredColumnBody == column_n) ? IM_COL32(255, 255, 128, 255) : IM_COL32(255, 0, 128, 255);
                    float thickness = (table->HoveredColumnBody == column_n) ? 3.0f : 1.0f;
                    draw_list->AddRect(r.Min, r.Max, col, 0.0f, 0, thickness);
                }
            }
            else
            {
                ImRect r = Funcs::GetTableRect(table, cfg->ShowTablesRectsType, -1);
                draw_list->AddRect(r.Min, r.Max, IM_COL32(255, 0, 128, 255));
            }
        }
    }

#ifdef IMGUI_HAS_DOCK
    // Overlay: Display Docking info
    if (cfg->ShowDockingNodes && g.IO.KeyCtrl && g.DebugHoveredDockNode)
    {
        char buf[64] = "";
        char* p = buf;
        ImGuiDockNode* node = g.DebugHoveredDockNode;
        ImDrawList* overlay_draw_list = node->HostWindow ? GetForegroundDrawList(node->HostWindow) : GetForegroundDrawList(GetMainViewport());
        p += ImFormatString(p, buf + IM_ARRAYSIZE(buf) - p, "DockId: %X%s\n", node->ID, node->IsCentralNode() ? " *CentralNode*" : "");
        p += ImFormatString(p, buf + IM_ARRAYSIZE(buf) - p, "WindowClass: %08X\n", node->WindowClass.ClassId);
        p += ImFormatString(p, buf + IM_ARRAYSIZE(buf) - p, "Size: (%.0f, %.0f)\n", node->Size.x, node->Size.y);
        p += ImFormatString(p, buf + IM_ARRAYSIZE(buf) - p, "SizeRef: (%.0f, %.0f)\n", node->SizeRef.x, node->SizeRef.y);
        int depth = DockNodeGetDepth(node);
        overlay_draw_list->AddRect(node->Pos + ImVec2(3, 3) * (float)depth, node->Pos + node->Size - ImVec2(3, 3) * (float)depth, IM_COL32(200, 100, 100, 255));
        ImVec2 pos = node->Pos + ImVec2(3, 3) * (float)depth;
        overlay_draw_list->AddRectFilled(pos - ImVec2(1, 1), pos + CalcTextSize(buf) + ImVec2(1, 1), IM_COL32(200, 100, 100, 255));
        overlay_draw_list->AddText(NULL, 0.0f, pos, IM_COL32(255, 255, 255, 255), buf);
    }
#endif // #ifdef IMGUI_HAS_DOCK

    End();
}

// [DEBUG] Display contents of Columns
void ImGui::DebugNodeColumns(ImGuiOldColumns* columns)
{
    if (!TreeNode((void*)(uintptr_t)columns->ID, "Columns Id: 0x%08X, Count: %d, Flags: 0x%04X", columns->ID, columns->Count, columns->Flags))
        return;
    BulletText("Width: %.1f (MinX: %.1f, MaxX: %.1f)", columns->OffMaxX - columns->OffMinX, columns->OffMinX, columns->OffMaxX);
    for (ImGuiOldColumnData& column : columns->Columns)
        BulletText("Column %02d: OffsetNorm %.3f (= %.1f px)", (int)columns->Columns.index_from_ptr(&column), column.OffsetNorm, GetColumnOffsetFromNorm(columns, column.OffsetNorm));
    TreePop();
}

static void DebugNodeDockNodeFlags(ImGuiDockNodeFlags* p_flags, const char* label, bool enabled)
{
    using namespace ImGui;
    PushID(label);
    PushStyleVar(ImGuiStyleVar_FramePadding, ImVec2(0.0f, 0.0f));
    Text("%s:", label);
    if (!enabled)
        BeginDisabled();
    CheckboxFlags("NoResize", p_flags, ImGuiDockNodeFlags_NoResize);
    CheckboxFlags("NoResizeX", p_flags, ImGuiDockNodeFlags_NoResizeX);
    CheckboxFlags("NoResizeY",p_flags, ImGuiDockNodeFlags_NoResizeY);
    CheckboxFlags("NoTabBar", p_flags, ImGuiDockNodeFlags_NoTabBar);
    CheckboxFlags("HiddenTabBar", p_flags, ImGuiDockNodeFlags_HiddenTabBar);
    CheckboxFlags("NoWindowMenuButton", p_flags, ImGuiDockNodeFlags_NoWindowMenuButton);
    CheckboxFlags("NoCloseButton", p_flags, ImGuiDockNodeFlags_NoCloseButton);
    CheckboxFlags("NoDocking", p_flags, ImGuiDockNodeFlags_NoDocking); // Multiple flags
    CheckboxFlags("NoDockingSplit", p_flags, ImGuiDockNodeFlags_NoDockingSplit);
    CheckboxFlags("NoDockingSplitOther", p_flags, ImGuiDockNodeFlags_NoDockingSplitOther);
    CheckboxFlags("NoDockingOver", p_flags, ImGuiDockNodeFlags_NoDockingOverMe);
    CheckboxFlags("NoDockingOverOther", p_flags, ImGuiDockNodeFlags_NoDockingOverOther);
    CheckboxFlags("NoDockingOverEmpty", p_flags, ImGuiDockNodeFlags_NoDockingOverEmpty);
    CheckboxFlags("NoUndocking", p_flags, ImGuiDockNodeFlags_NoUndocking);
    if (!enabled)
        EndDisabled();
    PopStyleVar();
    PopID();
}

// [DEBUG] Display contents of ImDockNode
void ImGui::DebugNodeDockNode(ImGuiDockNode* node, const char* label)
{
    ImGuiContext& g = *GImGui;
    const bool is_alive = (g.FrameCount - node->LastFrameAlive < 2);    // Submitted with ImGuiDockNodeFlags_KeepAliveOnly
    const bool is_active = (g.FrameCount - node->LastFrameActive < 2);  // Submitted
    if (!is_alive) { PushStyleColor(ImGuiCol_Text, GetStyleColorVec4(ImGuiCol_TextDisabled)); }
    bool open;
    ImGuiTreeNodeFlags tree_node_flags = node->IsFocused ? ImGuiTreeNodeFlags_Selected : ImGuiTreeNodeFlags_None;
    if (node->Windows.Size > 0)
        open = TreeNodeEx((void*)(intptr_t)node->ID, tree_node_flags, "%s 0x%04X%s: %d windows (vis: '%s')", label, node->ID, node->IsVisible ? "" : " (hidden)", node->Windows.Size, node->VisibleWindow ? node->VisibleWindow->Name : "NULL");
    else
        open = TreeNodeEx((void*)(intptr_t)node->ID, tree_node_flags, "%s 0x%04X%s: %s (vis: '%s')", label, node->ID, node->IsVisible ? "" : " (hidden)", (node->SplitAxis == ImGuiAxis_X) ? "horizontal split" : (node->SplitAxis == ImGuiAxis_Y) ? "vertical split" : "empty", node->VisibleWindow ? node->VisibleWindow->Name : "NULL");
    if (!is_alive) { PopStyleColor(); }
    if (is_active && IsItemHovered())
        if (ImGuiWindow* window = node->HostWindow ? node->HostWindow : node->VisibleWindow)
            GetForegroundDrawList(window)->AddRect(node->Pos, node->Pos + node->Size, IM_COL32(255, 255, 0, 255));
    if (open)
    {
        IM_ASSERT(node->ChildNodes[0] == NULL || node->ChildNodes[0]->ParentNode == node);
        IM_ASSERT(node->ChildNodes[1] == NULL || node->ChildNodes[1]->ParentNode == node);
        BulletText("Pos (%.0f,%.0f), Size (%.0f, %.0f) Ref (%.0f, %.0f)",
            node->Pos.x, node->Pos.y, node->Size.x, node->Size.y, node->SizeRef.x, node->SizeRef.y);
        DebugNodeWindow(node->HostWindow, "HostWindow");
        DebugNodeWindow(node->VisibleWindow, "VisibleWindow");
        BulletText("SelectedTabID: 0x%08X, LastFocusedNodeID: 0x%08X", node->SelectedTabId, node->LastFocusedNodeId);
        BulletText("Misc:%s%s%s%s%s%s%s",
            node->IsDockSpace() ? " IsDockSpace" : "",
            node->IsCentralNode() ? " IsCentralNode" : "",
            is_alive ? " IsAlive" : "", is_active ? " IsActive" : "", node->IsFocused ? " IsFocused" : "",
            node->WantLockSizeOnce ? " WantLockSizeOnce" : "",
            node->HasCentralNodeChild ? " HasCentralNodeChild" : "");
        if (TreeNode("flags", "Flags Merged: 0x%04X, Local: 0x%04X, InWindows: 0x%04X, Shared: 0x%04X", node->MergedFlags, node->LocalFlags, node->LocalFlagsInWindows, node->SharedFlags))
        {
            if (BeginTable("flags", 4))
            {
                TableNextColumn(); DebugNodeDockNodeFlags(&node->MergedFlags, "MergedFlags", false);
                TableNextColumn(); DebugNodeDockNodeFlags(&node->LocalFlags, "LocalFlags", true);
                TableNextColumn(); DebugNodeDockNodeFlags(&node->LocalFlagsInWindows, "LocalFlagsInWindows", false);
                TableNextColumn(); DebugNodeDockNodeFlags(&node->SharedFlags, "SharedFlags", true);
                EndTable();
            }
            TreePop();
        }
        if (node->ParentNode)
            DebugNodeDockNode(node->ParentNode, "ParentNode");
        if (node->ChildNodes[0])
            DebugNodeDockNode(node->ChildNodes[0], "Child[0]");
        if (node->ChildNodes[1])
            DebugNodeDockNode(node->ChildNodes[1], "Child[1]");
        if (node->TabBar)
            DebugNodeTabBar(node->TabBar, "TabBar");
        DebugNodeWindowsList(&node->Windows, "Windows");

        TreePop();
    }
}

// [DEBUG] Display contents of ImDrawList
// Note that both 'window' and 'viewport' may be NULL here. Viewport is generally null of destroyed popups which previously owned a viewport.
void ImGui::DebugNodeDrawList(ImGuiWindow* window, ImGuiViewportP* viewport, const ImDrawList* draw_list, const char* label)
{
    ImGuiContext& g = *GImGui;
    ImGuiMetricsConfig* cfg = &g.DebugMetricsConfig;
    int cmd_count = draw_list->CmdBuffer.Size;
    if (cmd_count > 0 && draw_list->CmdBuffer.back().ElemCount == 0 && draw_list->CmdBuffer.back().UserCallback == NULL)
        cmd_count--;
    bool node_open = TreeNode(draw_list, "%s: '%s' %d vtx, %d indices, %d cmds", label, draw_list->_OwnerName ? draw_list->_OwnerName : "", draw_list->VtxBuffer.Size, draw_list->IdxBuffer.Size, cmd_count);
    if (draw_list == GetWindowDrawList())
    {
        SameLine();
        TextColored(ImVec4(1.0f, 0.4f, 0.4f, 1.0f), "CURRENTLY APPENDING"); // Can't display stats for active draw list! (we don't have the data double-buffered)
        if (node_open)
            TreePop();
        return;
    }

    ImDrawList* fg_draw_list = viewport ? GetForegroundDrawList(viewport) : NULL; // Render additional visuals into the top-most draw list
    if (window && IsItemHovered() && fg_draw_list)
        fg_draw_list->AddRect(window->Pos, window->Pos + window->Size, IM_COL32(255, 255, 0, 255));
    if (!node_open)
        return;

    if (window && !window->WasActive)
        TextDisabled("Warning: owning Window is inactive. This DrawList is not being rendered!");

    for (const ImDrawCmd* pcmd = draw_list->CmdBuffer.Data; pcmd < draw_list->CmdBuffer.Data + cmd_count; pcmd++)
    {
        if (pcmd->UserCallback)
        {
            BulletText("Callback %p, user_data %p", pcmd->UserCallback, pcmd->UserCallbackData);
            continue;
        }

        char buf[300];
        ImFormatString(buf, IM_ARRAYSIZE(buf), "DrawCmd:%5d tris, Tex 0x%p, ClipRect (%4.0f,%4.0f)-(%4.0f,%4.0f)",
            pcmd->ElemCount / 3, (void*)(intptr_t)pcmd->TextureId,
            pcmd->ClipRect.x, pcmd->ClipRect.y, pcmd->ClipRect.z, pcmd->ClipRect.w);
        bool pcmd_node_open = TreeNode((void*)(pcmd - draw_list->CmdBuffer.begin()), "%s", buf);
        if (IsItemHovered() && (cfg->ShowDrawCmdMesh || cfg->ShowDrawCmdBoundingBoxes) && fg_draw_list)
            DebugNodeDrawCmdShowMeshAndBoundingBox(fg_draw_list, draw_list, pcmd, cfg->ShowDrawCmdMesh, cfg->ShowDrawCmdBoundingBoxes);
        if (!pcmd_node_open)
            continue;

        // Calculate approximate coverage area (touched pixel count)
        // This will be in pixels squared as long there's no post-scaling happening to the renderer output.
        const ImDrawIdx* idx_buffer = (draw_list->IdxBuffer.Size > 0) ? draw_list->IdxBuffer.Data : NULL;
        const ImDrawVert* vtx_buffer = draw_list->VtxBuffer.Data + pcmd->VtxOffset;
        float total_area = 0.0f;
        for (unsigned int idx_n = pcmd->IdxOffset; idx_n < pcmd->IdxOffset + pcmd->ElemCount; )
        {
            ImVec2 triangle[3];
            for (int n = 0; n < 3; n++, idx_n++)
                triangle[n] = vtx_buffer[idx_buffer ? idx_buffer[idx_n] : idx_n].pos;
            total_area += ImTriangleArea(triangle[0], triangle[1], triangle[2]);
        }

        // Display vertex information summary. Hover to get all triangles drawn in wire-frame
        ImFormatString(buf, IM_ARRAYSIZE(buf), "Mesh: ElemCount: %d, VtxOffset: +%d, IdxOffset: +%d, Area: ~%0.f px", pcmd->ElemCount, pcmd->VtxOffset, pcmd->IdxOffset, total_area);
        Selectable(buf);
        if (IsItemHovered() && fg_draw_list)
            DebugNodeDrawCmdShowMeshAndBoundingBox(fg_draw_list, draw_list, pcmd, true, false);

        // Display individual triangles/vertices. Hover on to get the corresponding triangle highlighted.
        ImGuiListClipper clipper;
        clipper.Begin(pcmd->ElemCount / 3); // Manually coarse clip our print out of individual vertices to save CPU, only items that may be visible.
        while (clipper.Step())
            for (int prim = clipper.DisplayStart, idx_i = pcmd->IdxOffset + clipper.DisplayStart * 3; prim < clipper.DisplayEnd; prim++)
            {
                char* buf_p = buf, * buf_end = buf + IM_ARRAYSIZE(buf);
                ImVec2 triangle[3];
                for (int n = 0; n < 3; n++, idx_i++)
                {
                    const ImDrawVert& v = vtx_buffer[idx_buffer ? idx_buffer[idx_i] : idx_i];
                    triangle[n] = v.pos;
                    buf_p += ImFormatString(buf_p, buf_end - buf_p, "%s %04d: pos (%8.2f,%8.2f), uv (%.6f,%.6f), col %08X\n",
                        (n == 0) ? "Vert:" : "     ", idx_i, v.pos.x, v.pos.y, v.uv.x, v.uv.y, v.col);
                }

                Selectable(buf, false);
                if (fg_draw_list && IsItemHovered())
                {
                    ImDrawListFlags backup_flags = fg_draw_list->Flags;
                    fg_draw_list->Flags &= ~ImDrawListFlags_AntiAliasedLines; // Disable AA on triangle outlines is more readable for very large and thin triangles.
                    fg_draw_list->AddPolyline(triangle, 3, IM_COL32(255, 255, 0, 255), ImDrawFlags_Closed, 1.0f);
                    fg_draw_list->Flags = backup_flags;
                }
            }
        TreePop();
    }
    TreePop();
}

// [DEBUG] Display mesh/aabb of a ImDrawCmd
void ImGui::DebugNodeDrawCmdShowMeshAndBoundingBox(ImDrawList* out_draw_list, const ImDrawList* draw_list, const ImDrawCmd* draw_cmd, bool show_mesh, bool show_aabb)
{
    IM_ASSERT(show_mesh || show_aabb);

    // Draw wire-frame version of all triangles
    ImRect clip_rect = draw_cmd->ClipRect;
    ImRect vtxs_rect(FLT_MAX, FLT_MAX, -FLT_MAX, -FLT_MAX);
    ImDrawListFlags backup_flags = out_draw_list->Flags;
    out_draw_list->Flags &= ~ImDrawListFlags_AntiAliasedLines; // Disable AA on triangle outlines is more readable for very large and thin triangles.
    for (unsigned int idx_n = draw_cmd->IdxOffset, idx_end = draw_cmd->IdxOffset + draw_cmd->ElemCount; idx_n < idx_end; )
    {
        ImDrawIdx* idx_buffer = (draw_list->IdxBuffer.Size > 0) ? draw_list->IdxBuffer.Data : NULL; // We don't hold on those pointers past iterations as ->AddPolyline() may invalidate them if out_draw_list==draw_list
        ImDrawVert* vtx_buffer = draw_list->VtxBuffer.Data + draw_cmd->VtxOffset;

        ImVec2 triangle[3];
        for (int n = 0; n < 3; n++, idx_n++)
            vtxs_rect.Add((triangle[n] = vtx_buffer[idx_buffer ? idx_buffer[idx_n] : idx_n].pos));
        if (show_mesh)
            out_draw_list->AddPolyline(triangle, 3, IM_COL32(255, 255, 0, 255), ImDrawFlags_Closed, 1.0f); // In yellow: mesh triangles
    }
    // Draw bounding boxes
    if (show_aabb)
    {
        out_draw_list->AddRect(ImTrunc(clip_rect.Min), ImTrunc(clip_rect.Max), IM_COL32(255, 0, 255, 255)); // In pink: clipping rectangle submitted to GPU
        out_draw_list->AddRect(ImTrunc(vtxs_rect.Min), ImTrunc(vtxs_rect.Max), IM_COL32(0, 255, 255, 255)); // In cyan: bounding box of triangles
    }
    out_draw_list->Flags = backup_flags;
}

// [DEBUG] Display details for a single font, called by ShowStyleEditor().
void ImGui::DebugNodeFont(ImFont* font)
{
    bool opened = TreeNode(font, "Font: \"%s\"\n%.2f px, %d glyphs, %d file(s)",
        font->ConfigData ? font->ConfigData[0].Name : "", font->FontSize, font->Glyphs.Size, font->ConfigDataCount);
    SameLine();
    if (SmallButton("Set as default"))
        GetIO().FontDefault = font;
    if (!opened)
        return;

    // Display preview text
    PushFont(font);
    Text("The quick brown fox jumps over the lazy dog");
    PopFont();

    // Display details
    SetNextItemWidth(GetFontSize() * 8);
    DragFloat("Font scale", &font->Scale, 0.005f, 0.3f, 2.0f, "%.1f");
    SameLine(); MetricsHelpMarker(
        "Note than the default embedded font is NOT meant to be scaled.\n\n"
        "Font are currently rendered into bitmaps at a given size at the time of building the atlas. "
        "You may oversample them to get some flexibility with scaling. "
        "You can also render at multiple sizes and select which one to use at runtime.\n\n"
        "(Glimmer of hope: the atlas system will be rewritten in the future to make scaling more flexible.)");
    Text("Ascent: %f, Descent: %f, Height: %f", font->Ascent, font->Descent, font->Ascent - font->Descent);
    char c_str[5];
    Text("Fallback character: '%s' (U+%04X)", ImTextCharToUtf8(c_str, font->FallbackChar), font->FallbackChar);
    Text("Ellipsis character: '%s' (U+%04X)", ImTextCharToUtf8(c_str, font->EllipsisChar), font->EllipsisChar);
    const int surface_sqrt = (int)ImSqrt((float)font->MetricsTotalSurface);
    Text("Texture Area: about %d px ~%dx%d px", font->MetricsTotalSurface, surface_sqrt, surface_sqrt);
    for (int config_i = 0; config_i < font->ConfigDataCount; config_i++)
        if (font->ConfigData)
            if (const ImFontConfig* cfg = &font->ConfigData[config_i])
                BulletText("Input %d: \'%s\', Oversample: (%d,%d), PixelSnapH: %d, Offset: (%.1f,%.1f)",
                    config_i, cfg->Name, cfg->OversampleH, cfg->OversampleV, cfg->PixelSnapH, cfg->GlyphOffset.x, cfg->GlyphOffset.y);

    // Display all glyphs of the fonts in separate pages of 256 characters
    if (TreeNode("Glyphs", "Glyphs (%d)", font->Glyphs.Size))
    {
        ImDrawList* draw_list = GetWindowDrawList();
        const ImU32 glyph_col = GetColorU32(ImGuiCol_Text);
        const float cell_size = font->FontSize * 1;
        const float cell_spacing = GetStyle().ItemSpacing.y;
        for (unsigned int base = 0; base <= IM_UNICODE_CODEPOINT_MAX; base += 256)
        {
            // Skip ahead if a large bunch of glyphs are not present in the font (test in chunks of 4k)
            // This is only a small optimization to reduce the number of iterations when IM_UNICODE_MAX_CODEPOINT
            // is large // (if ImWchar==ImWchar32 we will do at least about 272 queries here)
            if (!(base & 4095) && font->IsGlyphRangeUnused(base, base + 4095))
            {
                base += 4096 - 256;
                continue;
            }

            int count = 0;
            for (unsigned int n = 0; n < 256; n++)
                if (font->FindGlyphNoFallback((ImWchar)(base + n)))
                    count++;
            if (count <= 0)
                continue;
            if (!TreeNode((void*)(intptr_t)base, "U+%04X..U+%04X (%d %s)", base, base + 255, count, count > 1 ? "glyphs" : "glyph"))
                continue;

            // Draw a 16x16 grid of glyphs
            ImVec2 base_pos = GetCursorScreenPos();
            for (unsigned int n = 0; n < 256; n++)
            {
                // We use ImFont::RenderChar as a shortcut because we don't have UTF-8 conversion functions
                // available here and thus cannot easily generate a zero-terminated UTF-8 encoded string.
                ImVec2 cell_p1(base_pos.x + (n % 16) * (cell_size + cell_spacing), base_pos.y + (n / 16) * (cell_size + cell_spacing));
                ImVec2 cell_p2(cell_p1.x + cell_size, cell_p1.y + cell_size);
                const ImFontGlyph* glyph = font->FindGlyphNoFallback((ImWchar)(base + n));
                draw_list->AddRect(cell_p1, cell_p2, glyph ? IM_COL32(255, 255, 255, 100) : IM_COL32(255, 255, 255, 50));
                if (!glyph)
                    continue;
                font->RenderChar(draw_list, cell_size, cell_p1, glyph_col, (ImWchar)(base + n));
                if (IsMouseHoveringRect(cell_p1, cell_p2) && BeginTooltip())
                {
                    DebugNodeFontGlyph(font, glyph);
                    EndTooltip();
                }
            }
            Dummy(ImVec2((cell_size + cell_spacing) * 16, (cell_size + cell_spacing) * 16));
            TreePop();
        }
        TreePop();
    }
    TreePop();
}

void ImGui::DebugNodeFontGlyph(ImFont*, const ImFontGlyph* glyph)
{
    Text("Codepoint: U+%04X", glyph->Codepoint);
    Separator();
    Text("Visible: %d", glyph->Visible);
    Text("AdvanceX: %.1f", glyph->AdvanceX);
    Text("Pos: (%.2f,%.2f)->(%.2f,%.2f)", glyph->X0, glyph->Y0, glyph->X1, glyph->Y1);
    Text("UV: (%.3f,%.3f)->(%.3f,%.3f)", glyph->U0, glyph->V0, glyph->U1, glyph->V1);
}

// [DEBUG] Display contents of ImGuiStorage
void ImGui::DebugNodeStorage(ImGuiStorage* storage, const char* label)
{
    if (!TreeNode(label, "%s: %d entries, %d bytes", label, storage->Data.Size, storage->Data.size_in_bytes()))
        return;
    for (const ImGuiStorage::ImGuiStoragePair& p : storage->Data)
        BulletText("Key 0x%08X Value { i: %d }", p.key, p.val_i); // Important: we currently don't store a type, real value may not be integer.
    TreePop();
}

// [DEBUG] Display contents of ImGuiTabBar
void ImGui::DebugNodeTabBar(ImGuiTabBar* tab_bar, const char* label)
{
    // Standalone tab bars (not associated to docking/windows functionality) currently hold no discernible strings.
    char buf[256];
    char* p = buf;
    const char* buf_end = buf + IM_ARRAYSIZE(buf);
    const bool is_active = (tab_bar->PrevFrameVisible >= GetFrameCount() - 2);
    p += ImFormatString(p, buf_end - p, "%s 0x%08X (%d tabs)%s  {", label, tab_bar->ID, tab_bar->Tabs.Size, is_active ? "" : " *Inactive*");
    for (int tab_n = 0; tab_n < ImMin(tab_bar->Tabs.Size, 3); tab_n++)
    {
        ImGuiTabItem* tab = &tab_bar->Tabs[tab_n];
        p += ImFormatString(p, buf_end - p, "%s'%s'", tab_n > 0 ? ", " : "", TabBarGetTabName(tab_bar, tab));
    }
    p += ImFormatString(p, buf_end - p, (tab_bar->Tabs.Size > 3) ? " ... }" : " } ");
    if (!is_active) { PushStyleColor(ImGuiCol_Text, GetStyleColorVec4(ImGuiCol_TextDisabled)); }
    bool open = TreeNode(label, "%s", buf);
    if (!is_active) { PopStyleColor(); }
    if (is_active && IsItemHovered())
    {
        ImDrawList* draw_list = GetForegroundDrawList();
        draw_list->AddRect(tab_bar->BarRect.Min, tab_bar->BarRect.Max, IM_COL32(255, 255, 0, 255));
        draw_list->AddLine(ImVec2(tab_bar->ScrollingRectMinX, tab_bar->BarRect.Min.y), ImVec2(tab_bar->ScrollingRectMinX, tab_bar->BarRect.Max.y), IM_COL32(0, 255, 0, 255));
        draw_list->AddLine(ImVec2(tab_bar->ScrollingRectMaxX, tab_bar->BarRect.Min.y), ImVec2(tab_bar->ScrollingRectMaxX, tab_bar->BarRect.Max.y), IM_COL32(0, 255, 0, 255));
    }
    if (open)
    {
        for (int tab_n = 0; tab_n < tab_bar->Tabs.Size; tab_n++)
        {
            ImGuiTabItem* tab = &tab_bar->Tabs[tab_n];
            PushID(tab);
            if (SmallButton("<")) { TabBarQueueReorder(tab_bar, tab, -1); } SameLine(0, 2);
            if (SmallButton(">")) { TabBarQueueReorder(tab_bar, tab, +1); } SameLine();
            Text("%02d%c Tab 0x%08X '%s' Offset: %.2f, Width: %.2f/%.2f",
                tab_n, (tab->ID == tab_bar->SelectedTabId) ? '*' : ' ', tab->ID, TabBarGetTabName(tab_bar, tab), tab->Offset, tab->Width, tab->ContentWidth);
            PopID();
        }
        TreePop();
    }
}

void ImGui::DebugNodeViewport(ImGuiViewportP* viewport)
{
    SetNextItemOpen(true, ImGuiCond_Once);
    if (TreeNode((void*)(intptr_t)viewport->ID, "Viewport #%d, ID: 0x%08X, Parent: 0x%08X, Window: \"%s\"", viewport->Idx, viewport->ID, viewport->ParentViewportId, viewport->Window ? viewport->Window->Name : "N/A"))
    {
        ImGuiWindowFlags flags = viewport->Flags;
        BulletText("Main Pos: (%.0f,%.0f), Size: (%.0f,%.0f)\nWorkArea Offset Left: %.0f Top: %.0f, Right: %.0f, Bottom: %.0f\nMonitor: %d, DpiScale: %.0f%%",
            viewport->Pos.x, viewport->Pos.y, viewport->Size.x, viewport->Size.y,
            viewport->WorkOffsetMin.x, viewport->WorkOffsetMin.y, viewport->WorkOffsetMax.x, viewport->WorkOffsetMax.y,
            viewport->PlatformMonitor, viewport->DpiScale * 100.0f);
        if (viewport->Idx > 0) { SameLine(); if (SmallButton("Reset Pos")) { viewport->Pos = ImVec2(200, 200); viewport->UpdateWorkRect(); if (viewport->Window) viewport->Window->Pos = viewport->Pos; } }
        BulletText("Flags: 0x%04X =%s%s%s%s%s%s%s%s%s%s%s%s%s", viewport->Flags,
            //(flags & ImGuiViewportFlags_IsPlatformWindow) ? " IsPlatformWindow" : "", // Omitting because it is the standard
            (flags & ImGuiViewportFlags_IsPlatformMonitor) ? " IsPlatformMonitor" : "",
            (flags & ImGuiViewportFlags_IsMinimized) ? " IsMinimized" : "",
            (flags & ImGuiViewportFlags_IsFocused) ? " IsFocused" : "",
            (flags & ImGuiViewportFlags_OwnedByApp) ? " OwnedByApp" : "",
            (flags & ImGuiViewportFlags_NoDecoration) ? " NoDecoration" : "",
            (flags & ImGuiViewportFlags_NoTaskBarIcon) ? " NoTaskBarIcon" : "",
            (flags & ImGuiViewportFlags_NoFocusOnAppearing) ? " NoFocusOnAppearing" : "",
            (flags & ImGuiViewportFlags_NoFocusOnClick) ? " NoFocusOnClick" : "",
            (flags & ImGuiViewportFlags_NoInputs) ? " NoInputs" : "",
            (flags & ImGuiViewportFlags_NoRendererClear) ? " NoRendererClear" : "",
            (flags & ImGuiViewportFlags_NoAutoMerge) ? " NoAutoMerge" : "",
            (flags & ImGuiViewportFlags_TopMost) ? " TopMost" : "",
            (flags & ImGuiViewportFlags_CanHostOtherWindows) ? " CanHostOtherWindows" : "");
        for (ImDrawList* draw_list : viewport->DrawDataP.CmdLists)
            DebugNodeDrawList(NULL, viewport, draw_list, "DrawList");
        TreePop();
    }
}

void ImGui::DebugNodeWindow(ImGuiWindow* window, const char* label)
{
    if (window == NULL)
    {
        BulletText("%s: NULL", label);
        return;
    }

    ImGuiContext& g = *GImGui;
    const bool is_active = window->WasActive;
    ImGuiTreeNodeFlags tree_node_flags = (window == g.NavWindow) ? ImGuiTreeNodeFlags_Selected : ImGuiTreeNodeFlags_None;
    if (!is_active) { PushStyleColor(ImGuiCol_Text, GetStyleColorVec4(ImGuiCol_TextDisabled)); }
    const bool open = TreeNodeEx(label, tree_node_flags, "%s '%s'%s", label, window->Name, is_active ? "" : " *Inactive*");
    if (!is_active) { PopStyleColor(); }
    if (IsItemHovered() && is_active)
        GetForegroundDrawList(window)->AddRect(window->Pos, window->Pos + window->Size, IM_COL32(255, 255, 0, 255));
    if (!open)
        return;

    if (window->MemoryCompacted)
        TextDisabled("Note: some memory buffers have been compacted/freed.");

    ImGuiWindowFlags flags = window->Flags;
    DebugNodeDrawList(window, window->Viewport, window->DrawList, "DrawList");
    BulletText("Pos: (%.1f,%.1f), Size: (%.1f,%.1f), ContentSize (%.1f,%.1f) Ideal (%.1f,%.1f)", window->Pos.x, window->Pos.y, window->Size.x, window->Size.y, window->ContentSize.x, window->ContentSize.y, window->ContentSizeIdeal.x, window->ContentSizeIdeal.y);
    BulletText("Flags: 0x%08X (%s%s%s%s%s%s%s%s%s..)", flags,
        (flags & ImGuiWindowFlags_ChildWindow)  ? "Child " : "",      (flags & ImGuiWindowFlags_Tooltip)     ? "Tooltip "   : "",  (flags & ImGuiWindowFlags_Popup) ? "Popup " : "",
        (flags & ImGuiWindowFlags_Modal)        ? "Modal " : "",      (flags & ImGuiWindowFlags_ChildMenu)   ? "ChildMenu " : "",  (flags & ImGuiWindowFlags_NoSavedSettings) ? "NoSavedSettings " : "",
        (flags & ImGuiWindowFlags_NoMouseInputs)? "NoMouseInputs":"", (flags & ImGuiWindowFlags_NoNavInputs) ? "NoNavInputs" : "", (flags & ImGuiWindowFlags_AlwaysAutoResize) ? "AlwaysAutoResize" : "");
    BulletText("WindowClassId: 0x%08X", window->WindowClass.ClassId);
    BulletText("Scroll: (%.2f/%.2f,%.2f/%.2f) Scrollbar:%s%s", window->Scroll.x, window->ScrollMax.x, window->Scroll.y, window->ScrollMax.y, window->ScrollbarX ? "X" : "", window->ScrollbarY ? "Y" : "");
    BulletText("Active: %d/%d, WriteAccessed: %d, BeginOrderWithinContext: %d", window->Active, window->WasActive, window->WriteAccessed, (window->Active || window->WasActive) ? window->BeginOrderWithinContext : -1);
    BulletText("Appearing: %d, Hidden: %d (CanSkip %d Cannot %d), SkipItems: %d", window->Appearing, window->Hidden, window->HiddenFramesCanSkipItems, window->HiddenFramesCannotSkipItems, window->SkipItems);
    for (int layer = 0; layer < ImGuiNavLayer_COUNT; layer++)
    {
        ImRect r = window->NavRectRel[layer];
        if (r.Min.x >= r.Max.y && r.Min.y >= r.Max.y)
            BulletText("NavLastIds[%d]: 0x%08X", layer, window->NavLastIds[layer]);
        else
            BulletText("NavLastIds[%d]: 0x%08X at +(%.1f,%.1f)(%.1f,%.1f)", layer, window->NavLastIds[layer], r.Min.x, r.Min.y, r.Max.x, r.Max.y);
        DebugLocateItemOnHover(window->NavLastIds[layer]);
    }
    const ImVec2* pr = window->NavPreferredScoringPosRel;
    for (int layer = 0; layer < ImGuiNavLayer_COUNT; layer++)
        BulletText("NavPreferredScoringPosRel[%d] = {%.1f,%.1f)", layer, (pr[layer].x == FLT_MAX ? -99999.0f : pr[layer].x), (pr[layer].y == FLT_MAX ? -99999.0f : pr[layer].y)); // Display as 99999.0f so it looks neater.
    BulletText("NavLayersActiveMask: %X, NavLastChildNavWindow: %s", window->DC.NavLayersActiveMask, window->NavLastChildNavWindow ? window->NavLastChildNavWindow->Name : "NULL");

    BulletText("Viewport: %d%s, ViewportId: 0x%08X, ViewportPos: (%.1f,%.1f)", window->Viewport ? window->Viewport->Idx : -1, window->ViewportOwned ? " (Owned)" : "", window->ViewportId, window->ViewportPos.x, window->ViewportPos.y);
    BulletText("ViewportMonitor: %d", window->Viewport ? window->Viewport->PlatformMonitor : -1);
    BulletText("DockId: 0x%04X, DockOrder: %d, Act: %d, Vis: %d", window->DockId, window->DockOrder, window->DockIsActive, window->DockTabIsVisible);
    if (window->DockNode || window->DockNodeAsHost)
        DebugNodeDockNode(window->DockNodeAsHost ? window->DockNodeAsHost : window->DockNode, window->DockNodeAsHost ? "DockNodeAsHost" : "DockNode");

    if (window->RootWindow != window)       { DebugNodeWindow(window->RootWindow, "RootWindow"); }
    if (window->RootWindowDockTree != window->RootWindow) { DebugNodeWindow(window->RootWindowDockTree, "RootWindowDockTree"); }
    if (window->ParentWindow != NULL)       { DebugNodeWindow(window->ParentWindow, "ParentWindow"); }
    if (window->DC.ChildWindows.Size > 0)   { DebugNodeWindowsList(&window->DC.ChildWindows, "ChildWindows"); }
    if (window->ColumnsStorage.Size > 0 && TreeNode("Columns", "Columns sets (%d)", window->ColumnsStorage.Size))
    {
        for (ImGuiOldColumns& columns : window->ColumnsStorage)
            DebugNodeColumns(&columns);
        TreePop();
    }
    DebugNodeStorage(&window->StateStorage, "Storage");
    TreePop();
}

void ImGui::DebugNodeWindowSettings(ImGuiWindowSettings* settings)
{
    if (settings->WantDelete)
        BeginDisabled();
    Text("0x%08X \"%s\" Pos (%d,%d) Size (%d,%d) Collapsed=%d",
        settings->ID, settings->GetName(), settings->Pos.x, settings->Pos.y, settings->Size.x, settings->Size.y, settings->Collapsed);
    if (settings->WantDelete)
        EndDisabled();
}

void ImGui::DebugNodeWindowsList(ImVector<ImGuiWindow*>* windows, const char* label)
{
    if (!TreeNode(label, "%s (%d)", label, windows->Size))
        return;
    for (int i = windows->Size - 1; i >= 0; i--) // Iterate front to back
    {
        PushID((*windows)[i]);
        DebugNodeWindow((*windows)[i], "Window");
        PopID();
    }
    TreePop();
}

// FIXME-OPT: This is technically suboptimal, but it is simpler this way.
void ImGui::DebugNodeWindowsListByBeginStackParent(ImGuiWindow** windows, int windows_size, ImGuiWindow* parent_in_begin_stack)
{
    for (int i = 0; i < windows_size; i++)
    {
        ImGuiWindow* window = windows[i];
        if (window->ParentWindowInBeginStack != parent_in_begin_stack)
            continue;
        char buf[20];
        ImFormatString(buf, IM_ARRAYSIZE(buf), "[%04d] Window", window->BeginOrderWithinContext);
        //BulletText("[%04d] Window '%s'", window->BeginOrderWithinContext, window->Name);
        DebugNodeWindow(window, buf);
        Indent();
        DebugNodeWindowsListByBeginStackParent(windows + i + 1, windows_size - i - 1, window);
        Unindent();
    }
}

//-----------------------------------------------------------------------------
// [SECTION] DEBUG LOG WINDOW
//-----------------------------------------------------------------------------

void ImGui::DebugLog(const char* fmt, ...)
{
    va_list args;
    va_start(args, fmt);
    DebugLogV(fmt, args);
    va_end(args);
}

void ImGui::DebugLogV(const char* fmt, va_list args)
{
    ImGuiContext& g = *GImGui;
    const int old_size = g.DebugLogBuf.size();
    g.DebugLogBuf.appendf("[%05d] ", g.FrameCount);
    g.DebugLogBuf.appendfv(fmt, args);
    g.DebugLogIndex.append(g.DebugLogBuf.c_str(), old_size, g.DebugLogBuf.size());
    if (g.DebugLogFlags & ImGuiDebugLogFlags_OutputToTTY)
        IMGUI_DEBUG_PRINTF("%s", g.DebugLogBuf.begin() + old_size);
#ifdef IMGUI_ENABLE_TEST_ENGINE
    if (g.DebugLogFlags & ImGuiDebugLogFlags_OutputToTestEngine)
        IMGUI_TEST_ENGINE_LOG("%s", g.DebugLogBuf.begin() + old_size);
#endif
}

void ImGui::ShowDebugLogWindow(bool* p_open)
{
    ImGuiContext& g = *GImGui;
    if (!(g.NextWindowData.Flags & ImGuiNextWindowDataFlags_HasSize))
        SetNextWindowSize(ImVec2(0.0f, GetFontSize() * 12.0f), ImGuiCond_FirstUseEver);
    if (!Begin("Dear ImGui Debug Log", p_open) || GetCurrentWindow()->BeginCount > 1)
    {
        End();
        return;
    }

    CheckboxFlags("All", &g.DebugLogFlags, ImGuiDebugLogFlags_EventMask_);
    SameLine(); CheckboxFlags("ActiveId", &g.DebugLogFlags, ImGuiDebugLogFlags_EventActiveId);
    SameLine(); CheckboxFlags("Focus", &g.DebugLogFlags, ImGuiDebugLogFlags_EventFocus);
    SameLine(); CheckboxFlags("Popup", &g.DebugLogFlags, ImGuiDebugLogFlags_EventPopup);
    SameLine(); CheckboxFlags("Nav", &g.DebugLogFlags, ImGuiDebugLogFlags_EventNav);
    SameLine(); if (CheckboxFlags("Clipper", &g.DebugLogFlags, ImGuiDebugLogFlags_EventClipper)) { g.DebugLogClipperAutoDisableFrames = 2; } if (IsItemHovered()) SetTooltip("Clipper log auto-disabled after 2 frames");
    //SameLine(); CheckboxFlags("Selection", &g.DebugLogFlags, ImGuiDebugLogFlags_EventSelection);
    SameLine(); CheckboxFlags("IO", &g.DebugLogFlags, ImGuiDebugLogFlags_EventIO);
    SameLine(); CheckboxFlags("Docking", &g.DebugLogFlags, ImGuiDebugLogFlags_EventDocking);
    SameLine(); CheckboxFlags("Viewport", &g.DebugLogFlags, ImGuiDebugLogFlags_EventViewport);

    if (SmallButton("Clear"))
    {
        g.DebugLogBuf.clear();
        g.DebugLogIndex.clear();
    }
    SameLine();
    if (SmallButton("Copy"))
        SetClipboardText(g.DebugLogBuf.c_str());
    BeginChild("##log", ImVec2(0.0f, 0.0f), ImGuiChildFlags_Border, ImGuiWindowFlags_AlwaysVerticalScrollbar | ImGuiWindowFlags_AlwaysHorizontalScrollbar);

    ImGuiListClipper clipper;
    clipper.Begin(g.DebugLogIndex.size());
    while (clipper.Step())
        for (int line_no = clipper.DisplayStart; line_no < clipper.DisplayEnd; line_no++)
        {
            const char* line_begin = g.DebugLogIndex.get_line_begin(g.DebugLogBuf.c_str(), line_no);
            const char* line_end = g.DebugLogIndex.get_line_end(g.DebugLogBuf.c_str(), line_no);
            TextUnformatted(line_begin, line_end);
            ImRect text_rect = g.LastItemData.Rect;
            if (IsItemHovered())
                for (const char* p = line_begin; p <= line_end - 10; p++)
                {
                    ImGuiID id = 0;
                    if (p[0] != '0' || (p[1] != 'x' && p[1] != 'X') || sscanf(p + 2, "%X", &id) != 1)
                        continue;
                    ImVec2 p0 = CalcTextSize(line_begin, p);
                    ImVec2 p1 = CalcTextSize(p, p + 10);
                    g.LastItemData.Rect = ImRect(text_rect.Min + ImVec2(p0.x, 0.0f), text_rect.Min + ImVec2(p0.x + p1.x, p1.y));
                    if (IsMouseHoveringRect(g.LastItemData.Rect.Min, g.LastItemData.Rect.Max, true))
                        DebugLocateItemOnHover(id);
                    p += 10;
                }
        }
    if (GetScrollY() >= GetScrollMaxY())
        SetScrollHereY(1.0f);
    EndChild();

    End();
}

//-----------------------------------------------------------------------------
// [SECTION] OTHER DEBUG TOOLS (ITEM PICKER, ID STACK TOOL)
//-----------------------------------------------------------------------------

// Draw a small cross at current CursorPos in current window's DrawList
void ImGui::DebugDrawCursorPos(ImU32 col)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    ImVec2 pos = window->DC.CursorPos;
    window->DrawList->AddLine(ImVec2(pos.x, pos.y - 3.0f), ImVec2(pos.x, pos.y + 4.0f), col, 1.0f);
    window->DrawList->AddLine(ImVec2(pos.x - 3.0f, pos.y), ImVec2(pos.x + 4.0f, pos.y), col, 1.0f);
}

// Draw a 10px wide rectangle around CurposPos.x using Line Y1/Y2 in current window's DrawList
void ImGui::DebugDrawLineExtents(ImU32 col)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    float curr_x = window->DC.CursorPos.x;
    float line_y1 = (window->DC.IsSameLine ? window->DC.CursorPosPrevLine.y : window->DC.CursorPos.y);
    float line_y2 = line_y1 + (window->DC.IsSameLine ? window->DC.PrevLineSize.y : window->DC.CurrLineSize.y);
    window->DrawList->AddLine(ImVec2(curr_x - 5.0f, line_y1), ImVec2(curr_x + 5.0f, line_y1), col, 1.0f);
    window->DrawList->AddLine(ImVec2(curr_x - 0.5f, line_y1), ImVec2(curr_x - 0.5f, line_y2), col, 1.0f);
    window->DrawList->AddLine(ImVec2(curr_x - 5.0f, line_y2), ImVec2(curr_x + 5.0f, line_y2), col, 1.0f);
}

// Draw last item rect in ForegroundDrawList (so it is always visible)
void ImGui::DebugDrawItemRect(ImU32 col)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    GetForegroundDrawList(window)->AddRect(g.LastItemData.Rect.Min, g.LastItemData.Rect.Max, col);
}

// [DEBUG] Locate item position/rectangle given an ID.
static const ImU32 DEBUG_LOCATE_ITEM_COLOR = IM_COL32(0, 255, 0, 255);  // Green

void ImGui::DebugLocateItem(ImGuiID target_id)
{
    ImGuiContext& g = *GImGui;
    g.DebugLocateId = target_id;
    g.DebugLocateFrames = 2;
}

void ImGui::DebugLocateItemOnHover(ImGuiID target_id)
{
    if (target_id == 0 || !IsItemHovered(ImGuiHoveredFlags_AllowWhenBlockedByActiveItem | ImGuiHoveredFlags_AllowWhenBlockedByPopup))
        return;
    ImGuiContext& g = *GImGui;
    DebugLocateItem(target_id);
    GetForegroundDrawList(g.CurrentWindow)->AddRect(g.LastItemData.Rect.Min - ImVec2(3.0f, 3.0f), g.LastItemData.Rect.Max + ImVec2(3.0f, 3.0f), DEBUG_LOCATE_ITEM_COLOR);
}

void ImGui::DebugLocateItemResolveWithLastItem()
{
    ImGuiContext& g = *GImGui;
    ImGuiLastItemData item_data = g.LastItemData;
    g.DebugLocateId = 0;
    ImDrawList* draw_list = GetForegroundDrawList(g.CurrentWindow);
    ImRect r = item_data.Rect;
    r.Expand(3.0f);
    ImVec2 p1 = g.IO.MousePos;
    ImVec2 p2 = ImVec2((p1.x < r.Min.x) ? r.Min.x : (p1.x > r.Max.x) ? r.Max.x : p1.x, (p1.y < r.Min.y) ? r.Min.y : (p1.y > r.Max.y) ? r.Max.y : p1.y);
    draw_list->AddRect(r.Min, r.Max, DEBUG_LOCATE_ITEM_COLOR);
    draw_list->AddLine(p1, p2, DEBUG_LOCATE_ITEM_COLOR);
}

// [DEBUG] Item picker tool - start with DebugStartItemPicker() - useful to visually select an item and break into its call-stack.
void ImGui::UpdateDebugToolItemPicker()
{
    ImGuiContext& g = *GImGui;
    g.DebugItemPickerBreakId = 0;
    if (!g.DebugItemPickerActive)
        return;

    const ImGuiID hovered_id = g.HoveredIdPreviousFrame;
    SetMouseCursor(ImGuiMouseCursor_Hand);
    if (IsKeyPressed(ImGuiKey_Escape))
        g.DebugItemPickerActive = false;
    const bool change_mapping = g.IO.KeyMods == (ImGuiMod_Ctrl | ImGuiMod_Shift);
    if (!change_mapping && IsMouseClicked(g.DebugItemPickerMouseButton) && hovered_id)
    {
        g.DebugItemPickerBreakId = hovered_id;
        g.DebugItemPickerActive = false;
    }
    for (int mouse_button = 0; mouse_button < 3; mouse_button++)
        if (change_mapping && IsMouseClicked(mouse_button))
            g.DebugItemPickerMouseButton = (ImU8)mouse_button;
    SetNextWindowBgAlpha(0.70f);
    if (!BeginTooltip())
        return;
    Text("HoveredId: 0x%08X", hovered_id);
    Text("Press ESC to abort picking.");
    const char* mouse_button_names[] = { "Left", "Right", "Middle" };
    if (change_mapping)
        Text("Remap w/ Ctrl+Shift: click anywhere to select new mouse button.");
    else
        TextColored(GetStyleColorVec4(hovered_id ? ImGuiCol_Text : ImGuiCol_TextDisabled), "Click %s Button to break in debugger! (remap w/ Ctrl+Shift)", mouse_button_names[g.DebugItemPickerMouseButton]);
    EndTooltip();
}

// [DEBUG] ID Stack Tool: update queries. Called by NewFrame()
void ImGui::UpdateDebugToolStackQueries()
{
    ImGuiContext& g = *GImGui;
    ImGuiIDStackTool* tool = &g.DebugIDStackTool;

    // Clear hook when id stack tool is not visible
    g.DebugHookIdInfo = 0;
    if (g.FrameCount != tool->LastActiveFrame + 1)
        return;

    // Update queries. The steps are: -1: query Stack, >= 0: query each stack item
    // We can only perform 1 ID Info query every frame. This is designed so the GetID() tests are cheap and constant-time
    const ImGuiID query_id = g.HoveredIdPreviousFrame ? g.HoveredIdPreviousFrame : g.ActiveId;
    if (tool->QueryId != query_id)
    {
        tool->QueryId = query_id;
        tool->StackLevel = -1;
        tool->Results.resize(0);
    }
    if (query_id == 0)
        return;

    // Advance to next stack level when we got our result, or after 2 frames (in case we never get a result)
    int stack_level = tool->StackLevel;
    if (stack_level >= 0 && stack_level < tool->Results.Size)
        if (tool->Results[stack_level].QuerySuccess || tool->Results[stack_level].QueryFrameCount > 2)
            tool->StackLevel++;

    // Update hook
    stack_level = tool->StackLevel;
    if (stack_level == -1)
        g.DebugHookIdInfo = query_id;
    if (stack_level >= 0 && stack_level < tool->Results.Size)
    {
        g.DebugHookIdInfo = tool->Results[stack_level].ID;
        tool->Results[stack_level].QueryFrameCount++;
    }
}

// [DEBUG] ID Stack tool: hooks called by GetID() family functions
void ImGui::DebugHookIdInfo(ImGuiID id, ImGuiDataType data_type, const void* data_id, const void* data_id_end)
{
    ImGuiContext& g = *GImGui;
    ImGuiWindow* window = g.CurrentWindow;
    ImGuiIDStackTool* tool = &g.DebugIDStackTool;

    // Step 0: stack query
    // This assumes that the ID was computed with the current ID stack, which tends to be the case for our widget.
    if (tool->StackLevel == -1)
    {
        tool->StackLevel++;
        tool->Results.resize(window->IDStack.Size + 1, ImGuiStackLevelInfo());
        for (int n = 0; n < window->IDStack.Size + 1; n++)
            tool->Results[n].ID = (n < window->IDStack.Size) ? window->IDStack[n] : id;
        return;
    }

    // Step 1+: query for individual level
    IM_ASSERT(tool->StackLevel >= 0);
    if (tool->StackLevel != window->IDStack.Size)
        return;
    ImGuiStackLevelInfo* info = &tool->Results[tool->StackLevel];
    IM_ASSERT(info->ID == id && info->QueryFrameCount > 0);

    switch (data_type)
    {
    case ImGuiDataType_S32:
        ImFormatString(info->Desc, IM_ARRAYSIZE(info->Desc), "%d", (int)(intptr_t)data_id);
        break;
    case ImGuiDataType_String:
        ImFormatString(info->Desc, IM_ARRAYSIZE(info->Desc), "%.*s", data_id_end ? (int)((const char*)data_id_end - (const char*)data_id) : (int)strlen((const char*)data_id), (const char*)data_id);
        break;
    case ImGuiDataType_Pointer:
        ImFormatString(info->Desc, IM_ARRAYSIZE(info->Desc), "(void*)0x%p", data_id);
        break;
    case ImGuiDataType_ID:
        if (info->Desc[0] != 0) // PushOverrideID() is often used to avoid hashing twice, which would lead to 2 calls to DebugHookIdInfo(). We prioritize the first one.
            return;
        ImFormatString(info->Desc, IM_ARRAYSIZE(info->Desc), "0x%08X [override]", id);
        break;
    default:
        IM_ASSERT(0);
    }
    info->QuerySuccess = true;
    info->DataType = data_type;
}

static int StackToolFormatLevelInfo(ImGuiIDStackTool* tool, int n, bool format_for_ui, char* buf, size_t buf_size)
{
    ImGuiStackLevelInfo* info = &tool->Results[n];
    ImGuiWindow* window = (info->Desc[0] == 0 && n == 0) ? ImGui::FindWindowByID(info->ID) : NULL;
    if (window)                                                                 // Source: window name (because the root ID don't call GetID() and so doesn't get hooked)
        return ImFormatString(buf, buf_size, format_for_ui ? "\"%s\" [window]" : "%s", window->Name);
    if (info->QuerySuccess)                                                     // Source: GetID() hooks (prioritize over ItemInfo() because we frequently use patterns like: PushID(str), Button("") where they both have same id)
        return ImFormatString(buf, buf_size, (format_for_ui && info->DataType == ImGuiDataType_String) ? "\"%s\"" : "%s", info->Desc);
    if (tool->StackLevel < tool->Results.Size)                                  // Only start using fallback below when all queries are done, so during queries we don't flickering ??? markers.
        return (*buf = 0);
#ifdef IMGUI_ENABLE_TEST_ENGINE
    if (const char* label = ImGuiTestEngine_FindItemDebugLabel(GImGui, info->ID))   // Source: ImGuiTestEngine's ItemInfo()
        return ImFormatString(buf, buf_size, format_for_ui ? "??? \"%s\"" : "%s", label);
#endif
    return ImFormatString(buf, buf_size, "???");
}

// ID Stack Tool: Display UI
void ImGui::ShowIDStackToolWindow(bool* p_open)
{
    ImGuiContext& g = *GImGui;
    if (!(g.NextWindowData.Flags & ImGuiNextWindowDataFlags_HasSize))
        SetNextWindowSize(ImVec2(0.0f, GetFontSize() * 8.0f), ImGuiCond_FirstUseEver);
    if (!Begin("Dear ImGui ID Stack Tool", p_open) || GetCurrentWindow()->BeginCount > 1)
    {
        End();
        return;
    }

    // Display hovered/active status
    ImGuiIDStackTool* tool = &g.DebugIDStackTool;
    const ImGuiID hovered_id = g.HoveredIdPreviousFrame;
    const ImGuiID active_id = g.ActiveId;
#ifdef IMGUI_ENABLE_TEST_ENGINE
    Text("HoveredId: 0x%08X (\"%s\"), ActiveId:  0x%08X (\"%s\")", hovered_id, hovered_id ? ImGuiTestEngine_FindItemDebugLabel(&g, hovered_id) : "", active_id, active_id ? ImGuiTestEngine_FindItemDebugLabel(&g, active_id) : "");
#else
    Text("HoveredId: 0x%08X, ActiveId:  0x%08X", hovered_id, active_id);
#endif
    SameLine();
    MetricsHelpMarker("Hover an item with the mouse to display elements of the ID Stack leading to the item's final ID.\nEach level of the stack correspond to a PushID() call.\nAll levels of the stack are hashed together to make the final ID of a widget (ID displayed at the bottom level of the stack).\nRead FAQ entry about the ID stack for details.");

    // CTRL+C to copy path
    const float time_since_copy = (float)g.Time - tool->CopyToClipboardLastTime;
    Checkbox("Ctrl+C: copy path to clipboard", &tool->CopyToClipboardOnCtrlC);
    SameLine();
    TextColored((time_since_copy >= 0.0f && time_since_copy < 0.75f && ImFmod(time_since_copy, 0.25f) < 0.25f * 0.5f) ? ImVec4(1.f, 1.f, 0.3f, 1.f) : ImVec4(), "*COPIED*");
    if (tool->CopyToClipboardOnCtrlC && IsKeyDown(ImGuiMod_Ctrl) && IsKeyPressed(ImGuiKey_C))
    {
        tool->CopyToClipboardLastTime = (float)g.Time;
        char* p = g.TempBuffer.Data;
        char* p_end = p + g.TempBuffer.Size;
        for (int stack_n = 0; stack_n < tool->Results.Size && p + 3 < p_end; stack_n++)
        {
            *p++ = '/';
            char level_desc[256];
            StackToolFormatLevelInfo(tool, stack_n, false, level_desc, IM_ARRAYSIZE(level_desc));
            for (int n = 0; level_desc[n] && p + 2 < p_end; n++)
            {
                if (level_desc[n] == '/')
                    *p++ = '\\';
                *p++ = level_desc[n];
            }
        }
        *p = '\0';
        SetClipboardText(g.TempBuffer.Data);
    }

    // Display decorated stack
    tool->LastActiveFrame = g.FrameCount;
    if (tool->Results.Size > 0 && BeginTable("##table", 3, ImGuiTableFlags_Borders))
    {
        const float id_width = CalcTextSize("0xDDDDDDDD").x;
        TableSetupColumn("Seed", ImGuiTableColumnFlags_WidthFixed, id_width);
        TableSetupColumn("PushID", ImGuiTableColumnFlags_WidthStretch);
        TableSetupColumn("Result", ImGuiTableColumnFlags_WidthFixed, id_width);
        TableHeadersRow();
        for (int n = 0; n < tool->Results.Size; n++)
        {
            ImGuiStackLevelInfo* info = &tool->Results[n];
            TableNextColumn();
            Text("0x%08X", (n > 0) ? tool->Results[n - 1].ID : 0);
            TableNextColumn();
            StackToolFormatLevelInfo(tool, n, true, g.TempBuffer.Data, g.TempBuffer.Size);
            TextUnformatted(g.TempBuffer.Data);
            TableNextColumn();
            Text("0x%08X", info->ID);
            if (n == tool->Results.Size - 1)
                TableSetBgColor(ImGuiTableBgTarget_CellBg, GetColorU32(ImGuiCol_Header));
        }
        EndTable();
    }
    End();
}

#else

void ImGui::ShowMetricsWindow(bool*) {}
void ImGui::ShowFontAtlas(ImFontAtlas*) {}
void ImGui::DebugNodeColumns(ImGuiOldColumns*) {}
void ImGui::DebugNodeDrawList(ImGuiWindow*, ImGuiViewportP*, const ImDrawList*, const char*) {}
void ImGui::DebugNodeDrawCmdShowMeshAndBoundingBox(ImDrawList*, const ImDrawList*, const ImDrawCmd*, bool, bool) {}
void ImGui::DebugNodeFont(ImFont*) {}
void ImGui::DebugNodeStorage(ImGuiStorage*, const char*) {}
void ImGui::DebugNodeTabBar(ImGuiTabBar*, const char*) {}
void ImGui::DebugNodeWindow(ImGuiWindow*, const char*) {}
void ImGui::DebugNodeWindowSettings(ImGuiWindowSettings*) {}
void ImGui::DebugNodeWindowsList(ImVector<ImGuiWindow*>*, const char*) {}
void ImGui::DebugNodeViewport(ImGuiViewportP*) {}

void ImGui::DebugLog(const char*, ...) {}
void ImGui::DebugLogV(const char*, va_list) {}
void ImGui::ShowDebugLogWindow(bool*) {}
void ImGui::ShowIDStackToolWindow(bool*) {}
void ImGui::DebugHookIdInfo(ImGuiID, ImGuiDataType, const void*, const void*) {}
void ImGui::UpdateDebugToolItemPicker() {}
void ImGui::UpdateDebugToolStackQueries() {}

#endif // #ifndef IMGUI_DISABLE_DEBUG_TOOLS

//-----------------------------------------------------------------------------

// Include imgui_user.inl at the end of imgui.cpp to access private data/functions that aren't exposed.
// Prefer just including imgui_internal.h from your code rather than using this define. If a declaration is missing from imgui_internal.h add it or request it on the github.
#ifdef IMGUI_INCLUDE_IMGUI_USER_INL
#include "imgui_user.inl"
#endif

//-----------------------------------------------------------------------------

#endif // #ifndef IMGUI_DISABLE

Coverage Report

Created: 2023-11-19 01:17